First then, Obliquus Descendens seu Declivis.

This Muscle derives its Name fromVesalius prima Musculo­rum Ta­bula PP. the Progress of its Fibres. It arises with several acute Productions, partly Fleshy, and partly Tendinous, from the lower Margin of the fifth (n), sixth (o), [Page 19] seventh (p), and eighth Ribs (q), whereFig. xvii. its several seperate Originations lie be­tween the Indentations of the Serratus Major Anticus; These for better Di­stinction we chuse to call its former Origin; besides which it continues to derive more heads in like manner from the ninth (r), tenth (s), and eleventh (t), and sometimes from the extremity of the last Bastard Rib (u), where it is alsoFig. xvii. indented with the Serratus Inferior Posti­cus, Human. Corp. Tab. Lib. II. Cap. XXXI. as Vesalius has well observ'd: From its former Origin, its oblique des­cending Fleshy part expands it self in­to a broad Membranous Tendon, be­fore it marches over the Rectus to its Insertion in the Linea Alba and Os Pubis (38): From its latter in the same manner descending it ends partly Ten­dinous in the Ligamentum Pubis; but chiefly Fleshy on the superiour and forepart of the circular edge of the Os Ilium (36). It adheres not to theFig. xvii. Transverse Processes of the Vertebrae Human. Corp. Fab. Lib. IV. Cap. X. Syntag­ma Ana­tomica. Cap. II. Lumbares, as Spigelius, Veslingius, and with them most Anatomists have ima­gined. But its largest, last, and most Fleshy Digitation, leaving the lowest Bastard Rib at its extream Point, and in its oblique Descent de­clining [Page 20] forwards, still recedes gradu­ally more and more from the Verte­brae (34), forming a Triangular Inter­stice,Fig. xvii. comprehended by the Sacro­lumbus, Os Ilium (36), and its lower side; in which Area the Fibres of the subjacent Muscle plainly appear.

Besides the Actions vulgarly ascri­bed to this Muscle, and its Partner, together with the rest of their Fel­lows, viz. Compressing the Inte­stines and Bladder either in ex­cluding the Faeces and Urine in both Sexes, or Faetus in Women; They have still a farther and more Noble Use. That part of either of them that is interjacent between their latter Ori­gin and Spine of the Os Ilium (37), bearing an Analogy in its position to the Mastoideus of the Head, (of which hereafter) serves for the Circumro­tation of the Trunk upon the Axis of the Vertebrae, when we convert the Body to the contrary side, the Feet remaining unmov'd, for which neces­sary Motion Authors have assign'd noDe V [...]n­tricul. & Intestinis. Instrument, though this I think did not escape Dr. Glisson's Judicious Reflection.

[Page 21] For the better Dissection of these Abdo­minal Muscles, observe the following Me­thod. The Body being supported on its side, the Dorsi Latissimus of the con­trary must be Freed from its divers Fleshy Originations at the Curvated parts of the Ribs, as also the Tendinous part of it, which Arises from the edge of the Os Ilium: This done, the Blood being dried, and the Fat cleared, which caution (to prevent Confusion) must perpetually be ob­served, the Originations of the described Obliquus Descendens will appear.

Begin its Separation by Introducing your Fore Finger between it and the fol­lowing Muscle in the above noted Inter­stice, then Raise that Part of it which Springs from the Lowest Rib, and Ter­minates in the Spine of the Os Ilium, proceeding to Free the rest of its Digita­tions from between the four above-named Serrati, being cautious not to wound its Tendon in dividing it from its subjacent Muscle, especially as it marches over the Rectus. Nor may their Separation be attempted in every Subject by reason of their strict Adhesion; wherefore in prepa­ring these Muscles when they are to be De­monstrated after Dissection, you may pro­ceed in the following Order.

[Page 22] The Obliquus Descendens being Rais'd on either side (as before) to the Rectus, cut through and Raise both Tendons together, leaving them at their Insertions in the Linea Alba, taking sufficient care in their Separation from the Intersections of the Rectus. This done, on the contrary side Raise its▪ Fleshy part only, beginning in the Linea Semilunaris, by making an Aperture in its Tendon towards its Lower part, where it is separable from that of the following Muscle, thrusting a Probe between the Two Tendons, divide this Superiour one through the length of the Abdomen. Then, the Fleshy part on this side being also Rais'd, and clear'd to the Extremities of its Digitations and left there: Raise the oblique Ascendent; and on the same side you Rais'd the former towards its Origination, Raise this E Contrario, so pursuing it to the Linea Alba, where it is to be left: On the contra­ry side, its Fleshy Portion must be Rais'd to its Origination. The rest of these Muscles appearing in situ require no Dissection.

Obliquus Ascendens seu Acclivis.

So called from the oblique AscentSpigel. Tab. 10. Lib. 4. LL. of its Fibres, the same Error noted in the preceding Description is like­wise here committed by Vulgar Ana­tomists. Neither of these Muscles having any Communication with the Lumbal Vertebrae. It arises Fleshy from the whole circular edge of the Os Ilium (37), and Ligamentum Pubis, Fig. xvii. without any Thin Membrane spring­ing either from the Loins, or Os Sa­crum, Human Corp. Fab. Lib. II. CXXXI. as Vesalius would persuade us, or from the Apices of their Transverse Pro­cesses, as others pretend, thence mount­ing with an order of Fibres inclining Forwards, Forms a Broad Membra­nous Thin Tendon, Implanted into the whole length of the Linea Alba, and the Cartilages of the eighth (q),Fig. xvii. ninth (r), tenth (s), eleventh (t), and twelfth Ribs (u).

Besides its known Use in compres­sing the Abdomen and its Contents, that part of it which arises Fleshy towards the back part of the edge of the Os Ilium, by the oblique Ascent of its Fibres, to the Cartilaginious [Page 24] Endings of the Ribs, not only De­presses them and streightens the Ca­vity of the Thorax in Expiration, but in regard the Order of Fibres of this Intersect those of the Former Muscle, on the same side may Antagonise it in the Circumrotation of the Trunk of the Body on the Axis of the Vertebrae; as on its contrary side, its series of Fleshy Fibres being parallel to those of the said Descendens, on the oppo­site side may Act in Concurrence with it in discharge of its Office. In the Structure and Reciprocal Co-operati­on of these Muscles, the Ascending on the Right, and the Descending of the Left, Turning the Body to the Right, and Vice Versa. The Ascending in the Left and Descending in the Right in like manner Turning it to the Left, the Art of Nature indeed is very ad­mirable.

Pyramidalis vel Succenturiatus.

This Muscle lying on the Rectus Bidloo T. 32 Q. presents it self next in order of Dis­section. It has its Name from its Fi­gure aptly representing a Pyramid from a broad Basis ending in a Point. It [Page 25] Arises from the superior part of the Os Pubis (38), and in its Ascent lessens itsFig. xvii. self gradually till it becomes a long Tendon inserted in the Navel. Rio­lan Anthrop. lib. 5. cap. xxxiv. has observed the left to be most commonly the lesser, and if either be absent, it most usually is that; Fal­loppius Observat. Anatom. (who first discovered these Muscles) conjectures they compress the Bladder of Urin. Fabritius ab A­quapendente Vid. A­natom. Thom. Bartholin, lib. 1. cap. vi. imagines they support the Abdomen, and hinders the superior parts from pressing too violently on the inferior; but this Opinion seems to take its rise from observing the Ana­tomical subject in a supine Position. The Use, which we think most genuine and natural is this. When the Dia­phragm has prest the Viscera, whereby the Abdomen is become Tumid, these pull the Navel downwards, by which means they make a more adequate compression of the Bladder in the ex­pulsion of Urine, than any other Muscle of this part; though it must be confest they all contribute their as­sistance in that Action. They are cal­led Succenturiati by their Author, or Auxiliary Muscles from a supposition that they are only supplemental to the [Page 26] following in their action, the order of Fibres in both agreeing, and these be­ing always absent, when those are continued Fleshy to the Juncture of the Ossa Pubis.

Rectus.

So called from the Rectitude of its Position. Anatomists differ in assign­ing the Origination of this Muscle, some deriving it from the Sternum, others from the Os Pubis; but it seems a matter more of controversie than use, since either part is indifferently moved by it, the opposite remaining stable. Little can be added to the common and well known description of these Muscles, they being conti­nued according to the length of the Lower Belly from the Cartilago Ensi­formis (32), and two of the CartilagesFig. xvii. of the True, and two of the Bastard Ribs down to the Os Pubis (38), and divided into four or five Portions by three or four Intermediate Perigraphae, or Transverse Tendinous Intersections. The Vessels which pass underneath its Upper part are the Mammary Artery Descending, and its Vein Ascending. [Page 27] Those of its Lower part are the Epi­gastrick Artery Ascending, and its Vein Descending. The Inclosure of this Muscle in the double Tendon of the Ascendens we could never as yet dis­cern, rather suspecting that the Adhe­sion of the Ascending Tendon to that of the following Muscle in the Linea Semilunaris might occasion the mistake.

Transversalis.

So called because its Fibres run trans­versly over the Abdomen. This Muscle does not Arise according to the Vul­gar Tradition, from any Ligament, whither springing from the Os Sacrum, or covering the Sacrolumbus, but, as Realdus Columbus truly writes, fromDe Re Anato, lib. 5. cap. xxii. the Transverse Processes of the Lum­bal Vertebrae (34) Spine of the Os Ili­um Fig. xvii. (37), Ligamentum Pubis, and Car­tilaginious endings of the Ribs below the Sternum, from whence its Fleshy part passes over the Convex Sur­face of the Peritonaeum, and be­comes a Broad expanded Ten­don before it runs under the Rectus to its Implantation in the whole Longi­tude of the Linea Alba. When this [Page 26] [...] [Page 27] [...] [Page 28] Muscle with its Partner Act, they Press the Abdomen directly inwards, as in Expiration. Caspar Bartholin De Stru­ctura Dia­phrag­matis. Cap. ii. observes in Bulls and Animals of the larger size, that part of this Muscle is continuous with the Diaphragm at the Cartilaginious endings of the Ribs below the Sternum; whence he supposes the Diaphragma to be a Tri­gastrick Muscle. But whither this Observation will quadrate to a Hu­man Body whose Posture is Erect, and manner of Respiration different from that of Quadrupeds, we leave undecid­ed till farther Enquiries afford us bet­ter Information. The Spermatick Ves­sels pass through this and the Ascen­dant Muscle near the Inguina in the Mid-way between the Forepart of the Spine of the Os Ilium and Os Pubis, whence descending for some space be­tween the Fleshy part of the last named, and Tendon of the Obliquus Descendens, they run through a Fissure of the said Tendon near the last named Bone. These Perforations not exactly corresponding to each other, is an Ar­tifice in Nature to prevent a Prolapsus of the Intestines through them, not much unlike that oblique Insertion of the [Page 29] Uretres and Ductus Bilarius passing be­tween the Membranes of the Inte­stines and Bladder, whereby the retro­cession of the Bile in one, and the Urine in the other is prevented.

N. In the Dissection of these Muscles care must be taken not to wound the Cre­master on either side. The Peritonaeum with its Contents present themselves next to our Examination, but they not being Subjects of our present Enquiry, they must be all immediately removed for Reasons already mentioned. We proceed next to the Muscles of those parts, which for con­veniency in Dissection offer themselves next, namely, the Testes, Penis, Bladder of Urine, and Anus. The Body being laid with the Buttocks near the brink of the Table, and the Legs forcibly devarricated for the more commodious prosecution of the work, let the Operator place himself be­tween them, and continue the Division of the Skin, Fat, and Membranes by a Semi­circular Section on each side of the Pubes meeting in the Perinaeum near the Anus, and begin to raise the Skin of the upper part of the Penis, freeing it from the Spermatick Vessels, next raising that part which lies in the Perinaeum. This done, [Page 30] and the Fat removed, the following Muscles offer themselves to view.

Cremaster.

Or Suspensor Testiculi. It ArisesDe Graaf de Viro­rum Or­ganis T. 2. F. 1. CD. Fleshy from the Lowest and Forepart of the Spine of the Os Ilium (37) andFig. xv [...] Upper part of the Ligamentum Pubis, its Fibres running parallel with those of the Obliquus Ascendens, (not with the Transversalis as Bartholin objectsLib. 1. cap. xxii. against Riolan) and almost encompas­sing the Process of the Peritonaeum, des­cends on it to its Inferior part, which entertains the Testicle.

Its name declares its Office.

Acceleratores Urinae.

So called from their Use in expedi­ting the Ejection of Urine and Seed. Authors have been mistaken in the assigning the Originations of these Muscles, either to the Sphincter Ani or Tubercles of the Ossa Ischij. They Arising Fleshy from the superior part of the Urethra, as it passes under the Ossa Pubis, and encompassing the Ex­ternal part of the Bulb of its Caver­nous Body (CC) (mentioned in ourFig. xii. Appendix). Both Muscles meet on the Inferior part, (bb) and march ac­cording to the length of the seam of [Page 32] the skin in the Perinaeum, parting from each other (cc) They Ascend to theirFig. xii. Insertions on each side the Corpora Ca­vernosa Penis (GG).

Besides the Use commonly ascribed to these Muscles in compressing the Urethra in driving out the Remains of Urine, and promoting the Ejacula­tion of the Semen in Coitu, (which Action is chiefly done by the last de­scribed Part of them embracing the Urethra as they pass to their Inserti­ons on each side the Cavernous Bodies of the Penis) They also assist the fol­lowing Muscles in Its Erection, by driving the Blood contained in the Bulb of the Cavernous Body of the Ure­thra (A) towards the Glans in greaterFig. xiv. quantities, whereby it becomes di­stended, the Veins which carry off the Refluent Blood from the Corpus Cavernosum Urethrae at that time being also comprest by the Tumefaction of these Muscles.

Erectores Penis seu Erigentes.

By some called Directores, and by Spigelius, Collaterales Penis. They AriseLib. 4. cap. xii. Fleshy from the External Knob of the [Page 33] Os Ischium (39) below the beginningsFig. xvii. of the Cavernous Bodies of the Penis, in whose thick Membrane they are Inserted. (DD).Fig. x. Fig. xii. F F.

When these Muscles Act they pull the Penis towards the Ossa Pubis, where­by its great Vein is comprest, and the Refluent Blood denied its passage un­der those Bones, by which means the Penis is Erected, of which, hereafter we shall give a more full Account.

Transversalis Penis.

So called from their situation. These are mentioned by Lindanus after Aquapendens, as * Thom. Bartholin takesLib. 1. cap. xxiv. notice. They Arise near the Former, from whence they pass Transversly to their Insertions at the upper part of the Bull of the Cavernous body of the Urethra. (EE.)Fig. x, and xii.

To these may be added the Muscles of the Clitoris, and that of the Pu­dendum in Women.

Anatomists differ concerning the number of these Muscles belonging to the Clitoris, some with Falloppius Observat. Anatom. (who first Observed them) reckon One [Page 34] Pair only; Others Two; but De De Mulie­rum Or­ganis, &c Graaf inclines to the First Opinion, which we also think most agreeable to Truth. Authors have not bestowed any Proper Names on them, but since they agree so exactly with the Ere­ctores Penis (above Treated of) except in point of Magnitude; The same Apellations may also serve here.

Erector Clitoridis.

This Arises Fleshy from the Exter­nalDe Gaaf de Mulie­rum Org. T. xl ii. T. iii. F. l. GG. Margin of the Os Ischium (39), andFig. xv [...] is Implanted into the Beginning of the Cavernous Body of the Clitoris.

The Action and Use of This and its Partner is the same with the Ere­ctores Penis. The other Pair of Muscles ascribed to this Part by Vul­gar Anatomists, and Figured by De Graaf, are a Portion of the Following, adhering to it.

Sphincter Vaginae.

This lies immediately under theIbid. e e. and T. iii. F. 28. EE. Clitoris, incompassing the Vagina with Circular Fibres, Three Fingers in Breadth; in some Subjects, it scarcely appeareth Fleshy.

[Page 35]This Acting not only streightens the Vagina, but thereby also it hin­ders the Blood in its return from the Plexus Retiformis, of the Pudendum; by compressing some of its subjacent Veins which pass un­derneath, by which means the Labia become Distended, and Vagina Con­tracted.

Detrusor Urinae.

This by some is reckoned the FirstSpigel. Lib. viii. T. 13. MM. Proper Membrane of the Bladder, lying under that which is derived from the Peritonaeum; its Carnous Fibres embracing the whole Bladder like a Hand (as Spigelius represents it)Lib. iv. cap. 12. [Page 36] compresses it in the Evacuation of the Urine.

Sphincter Vesiicae.

Fallopius observes, that the Anato­mistsObservat. Anatom. of his Age had not well De­scribed this Muscle in placing it be­low the Prostatoe, in which case as he alledges the Semen in the Venereal Act could not be emitted without the Urine; which Observation latter Au­thors have not taken notice of, ei­ther through inadvertency in Disse­ction, or being imposed on by Part of the Levatores Ani, which remained on the Prostates, which Riolan calls theAnthrop. Lib. v. C. xxxvii. Sphincter Externus. It is seated in the upper part of the neck of the Bladder, immediately above the Glandulae Pro­statae, ‘"Where (as Fallopius says)Observat. Anatom. you must not expect to find an en­tire Muscle and Substance distinct from the Subject Cannal, like that of the Anus, but the more Fleshy part of the neck of the Bladder com­posed of many Transverse Fibres, whose Contraction hinders the Invo­luntary Egress of the Urine."’

[Page 37] N. To discover these Transverse Fibres, our Author advises to Immerge the Blad­der in scalding Water after Inflation, the External Right Fibres being removed These will appear underneath.

Sphincter Ani.

This is a Large, Thick, Fleshy Muscle encompassing the Anus; its Figure and Series of Fibres External­ly, immediately under the Skin, in­clineFig. xii. to an ablong Oval; It is Con­nected Forwards to the Accelerator Urinae (D) (as above noted); Back­wards to the Os Coccygis; As it is conti­nued farther upon the Body of the In­testinum Rectum; its Fibres are Circu­lar for near Two Inches in Breadth; it is much larger in Man than in other Animals, in whom by reason of the erect Position of the Body, there is greater Force required to Retain the Faeces, which is the Office of this Muscle.

Levatores Ani.

Riolan reprehends Spigelius for hisAnimad. in lib. Anatom. Spigelii. Description of these Muscles. They Arise Fleshy from each side the Ossa Pubis, internally within the Pelvis (33),Fig. xviii. as also from part of the Os Ischium (31) and Sacrum (O); from these Places, like Lines drawn from a Cir­cumference [Page 39] towards a Centre, its Fibres Descend over the Musculi Mar­supiales, to their Implantation at the Lower end of the Intestinum Rectum in the Anus. The Use of these Muscles is chiefly to Suspend and Draw the Anus Upwards, lest the Faecis should be burthensom to the Sphincter. In their Descent on each side Forwards from the Ossa Pubis they Pass close over the Glandulae Prostatoe, in a man­ner embracing them (as before) by which Mechanism they are rendred capable of Compressing them; and by Retraction of the Anus at the same time Act on the Vesiculoe Seminales, in order to promote the Emission of the Seed in Coitu. We proceed next to the Muscles of the Hairy-scalp, &c.

Occipitalis.

This and its Partner are mentioned by Columbus, and Accurately Describ­edLib. v. cap. vii. Observat. Anatom. by Falloppius; They are Short, but Broad, Thin, Fleshy Muscles, situated on the Occiput, from whence they De­rive their Names; each of these Arises Fleshy from that Part of the Os Occi­pitis Fig. xviii. [Page 41] where the Mastoideus and Muscu­lus Splenius are Inserted, and soon be­coming Tendinous joins with the Pe­ricranium, which firmly adheres to the Hairy-scalp on the Sinciput. When these Act, they pull the Hairy-scalp Backwards.

Frontalis.

This Arises Thin, Broad, and Fleshy, from the Upper part of the Os Frontis near the Sutara Coronalis, and Descend­ing by the Posterior and Fore part of the Temporalis, meets with its Partner near their Insertions to the Skin of the Eye-brows. (AA.)Fig. i.

These Acting draw up and wrinkle the Skin of the Forehead, and cannot Antagonise the Former Muscles, as some Imagine, since their Originati­ons is from the Bone Above, and their Terminations in the Skin of the Lower part of the Forehead.

Besides these, Volcherus Coiter countsObservat. Anatom. another Pair, which later Authors call Corrugatores, Arising near each Great Canthus of the Eye at the Puncta Lachrymalia; seeming to Terminate about the Middle Region of the Eye­brows. [Page 42] But We rather incline to the Opinion of Others, who take them to be Two Oblique Elongations of the Former Muscles.

N. To raise the Skin, and discover the Muscles of the Face, which in the Order of Dissection are next to be prosecuted, continue your Former Division from the Dorsum Nasi where you before left it, to its Apex, from Two Semicircular Secti­ons on each side the Alae Nasi to the Sep­tum Narium, make a direct one to join with a Circular Incision about the Lips, and from the middle of that of the Lower Lip, draw your Knife directly over the Chin Neck and Sternum till you meet that lon­gitudinal one made in Dissection of the Muscles of the Abdomen. The Skin is best cleared from the Eyelids, after Raising it from the circumambient parts. In the Practice of this Operation, special Atten­tion must be had, lest you wound the Orbi­cularis Palpebrarum; Care also must be taken in Raising the Skin of the Neck, and Face, not to raise the Quadratus Genae with it.

Orbicularis Palpebrarum.

This is a Thin Fleshy Muscle, whose Fibres do Circularly environ the Eye-Lids BB, and are Inserted toFig. i. them, (like the Sphincter Labiorum) not adhering to any Bone, from whence we may derive their Origin, except the Superiour part of the great Bone of the Nose; by some reckoned the fourth Bone of the Upper Jaw.

This Muscle Acting like the Sphin­cters of other Parts, Constringes the Eye-Lids. To these Riolan adds ano­therAnthro­pog. Lib. V. Cap. X Muscle belonging to each Eye-Lid, which he calls Ciliaris, which we take to be a Portion of the former adjacent to the Cilia.

To discover the following Muscle, that part of the former, lying between the Upper Eye-Lid and Eyebrow, must be Raised; After which, the Glandula [Page 45] Lachrimalis, with part of the Fat with­in the Orbit being removed, by extending the Upper Eye-Lid, either with a Hook, or your Fingers only, its Tendinous In­sertion and slender Fleshy Body will appear.

Aperiens Palpebram Rectus.

So called from its streight ProgressBid. T. 12. F. 4. A. and Use. It Arises Sharp and Fleshy from the profoundest part of the Orbit, near the place where the Op­tick Nerve is Transmitted, passing directly over the Musculus Attollens it becomes Tendinous as it marches over the Bulb of the Eye; whence growing still Broader and Thinner, till it is Inserted to the whole Supe­riour part of the Upper Eye-Lid.

These Muscles of the Eye-Lids being Hyron. F brit. De Visio­ne. Cap. XI. removed, we proceed next to those of the Eye it self; in the Demonstration of which, Aquapendens proposes two ways; the one shewing the Eye with its Muscles in situ, the other the Eye taken out of its Cavity, and its Muscles expanded on the Table: The First exhibiting their Motions, the Second their Figure or Shape. In the First, though our Author advises the Brain to be taken out, and the Bones of [Page 46] the Orbit divided; yet we chuse to per­form this Operation in the following man­ner, without troubling our selves with either. Both Eye-Lids being removed, first, with your Fore-Finger feel gently for the Trochlea, situated near the brink of the Orbit (o), towards the Nose; then Fig. iii. clear the Tendon which passes through it: This done in like manner clear the Oppo­site Muscle, the Obliquus Inferior, first observing its Origination at the brink of the Inferior part of the Orbit (e), with Fig. iii. the Assistance of a small Hook and Scissars▪ extract the Fat and Membranes, and Vessels from between the streight Muscles. The other manner of Demonstration may be Practised in the same Eye, or with the contrary, taking Care in dividing the Trochlea from the Orbit, to prevent Wounding the Tendon, which passes through it; The Inferiour Oblique Muscle being cut off close from its Origin, as also the rest of the Muscles, and Optick Nerve at the profoundest part of the Orbit, and the whole Eye dislodg'd; Disingage its Mus­cles, and display them, whereby you may observe, that the Trochlearis is the longest Muscle of the Eye; and that its Insertion is directly behind the Attollens; and on the contrary, the Obliquus Inferior is [Page 47] the shortest, whose Termination is directly behind the Abducens, by which means you may distinguish each, and find the side to which it belongs.

Obliquus Superior or Trochlearis.

It receives its first Denomination from its Oblique Position and Course, in regard of the rest of its Fellows. [Page 48] The Second, it derives from that Car­tilaginous Ring, suspended near the Brink of the upper Part of the Orbit towards the Nose (o) through whichFig. iii. its Tendon passes, being reflected on it, as a Rope on a Pully: (A) Be­sidesFig. ii. which, it is called Longissimus Oculi, as exceeding the others in length. It arises sharp, and Fleshy from the profoundest Part of the Or­bit, near the Origination of the Abdu­cens, and becoming a Fleshy Belly (D) as it passes Obliquely close under its Superior Part, makes a round Ten­don running through the Trochlea (as above mentioned) from whence rever­ting back (A) its inserted to the Tuni­ca Sclerotis, in the middle of the Di­stance between the Termination of the Attollens, and Optick Nerve, towards the back Part of the Bulb of the Eye. (A)

Obliquus Inferior.

Also called Brevissimus Oculi, it be­ing the shortest Muscle of the Eye. This springs sharp and fleshy from immediately within the Lower, and almost outward Part of the Orbit (e), atFig. iii. [Page 49] the Juncture of the First Bone of the Upper Jaw (6), with the Fourth (5.),Fig. xvii. becoming Thicker Ascends Obliquely over the Deprimens, growing Tendi­nous at its Insertion to the Tunica Sclerotis near the Implantation of the Former, directly betwixt the Abdu­cens and Optick Nerve. (I.)Fig. ii.

These two Oblique Muscles are by some called Circumagentes, and Ama­torii from their Actions in Winding and Rolling the Eye about, which Motions we call Ogling. Anatomists differ in assigning the Proper Offices of these Muscles, some asserting when the Superior Acts, the Eye is Rolled from the Nose, when the Inferior, to it: Others on the contrary, suppose that the Former Draws it to the Nose, and the Latter Directs it towards the Lesser Canthus of the Eye. But if we rightly consider the Position of the Trochlea (o), which determinesFig. iii. the Motion made by the Superior Oblique Muscle, and the Origination of the Inferior (e), and that the Tendon of the Former, and the whole Ductus of the Latter pass Obliquely from the External edge of the Orbit to their Insertions at the Back part of [Page 50] the Bulb of the Eye, as exprest Fig. ii. We must necessarily conceive, that the Vulgar Doctrines of their Motions are Erroneous: wherefore if the Ob­liquus Superior Acts, the Posteriour Part of the Bulb of the Eye must ap­proach towards the Trochlea, whereby its Globe is not only drawn some­what Forwards, but its Pupil is di­rected downwards; so on the contra­ry, when the Obliquus Inferior Acts, the Posterior part of the Bulb of the Eye approaches towards the External edge of the Inferior part of the Orbit; and its Pupil is directed Upwards, and its whole Globe Pulled somewhat out­wards. Hence it is that the Bulb of the Eye is more Protuberant in those Actions, which Contrivance in Na­ture seems very necessary, since the Projections of the Eyebrows and Cheeks would be liable to hinder our Prospect, whether directly Upwards or Downwards: Besides the Uses of these Oblique Muscles now mention­ed, they have still a more notable one, not only in pulling the whole Eye directly Forwards, but they hold it from being Retracted, when any of the Four Streight Muscles Act, which [Page 51] otherwise would rather draw it In­wards, then turn it either Sideways, or Upwards, or Downwards. But these Muscles, one of them Descend­ing inwardly from the Uppermost, and the other Ascending from the Lowermost edge of the Orbit to their Insertions, in effect not unlike an Axis, prevent its being Retracted. Hence it is when they cease to Act, the whole Globe of the Eye sinks, which may give Occasion for that Vulgar Tradition, that the Eye­strings break in Dying Persons.

The rest of the Muscles of the Eye are called Recti from their Streight Progress and Use.

Elevator Oculi.

It is also called Superbus from its moral signification, it being one of the chief common marks of a Haughty Disposition to look high; wherefore its Opposite Muscle is called Humilis; but Placentinus thinks the Motions ofCasserius, Lib. v. C. xviii. the Upper Eyelids denote those Dis­positions more significantly, for says he, Qui enim hanc elatam habent, (speak­ing of the Upper Eyelids) Superbi & [Page 52] Feroces sunt; qui vero Depressam ac dimi­dium fere Oculum Claudentem, ita ut Ter­ram adspicere videantur, Humiles ac Mites sunt. This Muscle Arises Sharp, and Fleshy, near the place where the Optick Nerve enters the Orbit, and becoming a Fleshy Belly makes a Thin Tendon Inserted to the Tunica Sclerotis on the Superior and Forepart of the Bulb of the Eye under the Adnata. (E.)Fig. ii.

Depressor Oculi.

This, like the Former, Arises from the Profoundest Part of the Orbit, and like it passes directly to its Insertion to the Opposite part of the Globe of the Eye. (G.)Fig. ii.

Adductor Oculi.

So called because it inclines its Pu­pil towards the Nose, and Bibitorius, it directing the Eye towards the Cup. The Origin and Progress of This is agreeable with the Two Former, and is Inserted to that part of the Tunica Sclerotis bordering on the Nose. (H. Fig. ii.

Abductor Oculi.

So called from its Action in Re­tracting the Eye from the Nose; it is also called Indignabundus, because it is made use of in scornful resentments. This like the Three Former Arises where the Optick Nerve is Trans­mitted; and is Inserted like Them to that part of the Tunica Sclerotis, that respects the Lesser Canthus of the Eye, Opposite to the Implantation of the Former (F). When these Four RightFig. ii. Muscles Act together, They Pull the whole Globe of the Eye into the Or­bit, from whence it's Pull'd Forwards again by the Two Obliqui as before.

To these Mullinete adds another,Dissertat. Anatom. Cap. vi. which he calls the Fifth Right Muscle; the Office of which he confines to the Motion of the Trochlea, (supposing it moveable) but what he has said con­cerning it either as to its Existence or Use is so Obscure, if not Impossible, that We can see no Reason to give it any place or description amongst those other Muscles of the Eye. Neither could we ever discover by Dissection any such Muscle, but we suspect [Page 54] that part of the Orbicularis Palpebrarum, which adheres to the Trochlea, might occasion the Mistake, which I rather remark, because I find others upon Mullinete's Authority, without strict enquiry into the Matter, have fallen into the same Error.

Dilatores Alarum Nasi.

These are Small Thin Muscles, ha­ving a double Order of Fibres decus­sating each other, not unlike the Mus­culi Intercostales: They Arise from the Inferior and Internal parts of the Ossa Narium, and are soon Inserted to the superior parts of the Alae. These pull up the Alae and Dilate the Nostrils; but I am apt to think they are not found in all subjects.

Retractores Alarum Nasi & Elevatores Labii Superioris.

These were mentioned by Galen; They Arise Broad and Fleshy from the Fourth Bone of the Upper Jaw (5),Fig. xvii. whence descending obliquely they are soon Inserted to the Upper Lip and Alae Nasi. (C.)Fig. i.

The Constrictor Alae Nasi mentioned by Falloppius and Placentinus, we sus­pect to be altogether Fictitious.

Constrictores Alarum Nasi ac Depressores Labii Superioris.

These Arise Fleshy from the Fore­parts of the Fourth Bones of the Up­per Jaw, immediately above the Gums of the Dentes Incisorii, and ascending, are soon Inserted to the roots of the Alae Nasi, and superior parts of the Upper Lip. (D.)Fig. iii.

When these Act they draw the Up­per Lip and Alae downwards; by which means they bring the latter nearer each other. Hence, when we attempt the Reception of any Odori­ferous Effluvia, the Upper Lip is pul­led downwards.

Quadratus Genae, seu Tetragonus.

By Galen called Platusma Muoides, De Mus. Cap. ii. or the Muscular expansion. This is a great square Muscle lying under the skin of the Neck, and is spread over the whole Inferior Region of the Face. It Arises Thin and Membranous, ac­cording to Galen, from the Spines of the Vertebrae of the Neck; It also springs from the skin on the superior part of the Cuccularis, and Pectoral Muscle, from hence ascending under the skin of the Neck becomes Fleshy, and one part adhering to the Os Hy­oides, is soon Inserted to the Middle of the Lower Jaw; The other Broader portion proceeding farther to its Im­plantation in the Cheeks below the Angle of the Lips.

[Page 59]When both these Muscles Act, they pull down each Angle of the Mouth, together with the Cheeks, which Po­sture of the Face is the proper Expres­sion of Sorrow. But if the Inferior Parts of these Muscles (which lie on the Neck) Act alone, they distend the superincumbent skin by making it Aproach to a Direct Line with the Claviculae (14) and Lower Jaw BoneFig. xvii. (10), which otherwise is Indented according to the Formation of the part, where by a Double Chin (as they call it) is Represented.

Buccinator.

So called because in Trumpeters it Forces out the Breath. This Muscle does not spring from the Gums of the Upper, and end in those of the Nether Jaw; nor is it of that Figure which Vulgar Anatomists would per­swade Us; or Intertext with various Orders of Fibres, as others Pretend. It Arises Broad and Fleshy from the Forepart of the Processus Corone (B) ofFig. iv. the Lower Jaw Bone, from hence proceeding with direct Fibres it ad­heres to the Gums of Both Jaws, [Page 60] and is so Inserted to the Angle of the Lips. (K.)Fig. i.

Through the middle of this Muscle Passes the Ductus Salivalis superior (d), which Placentinus had observed andTheat. Anatom. Lib. iii. Cap. lxix. called Vinculum robustum (as Casper Bauhin writes.) Besides the Use Trum­peters makes of this Muscle, it also pulls the Lips or Mouth to one side.

The Muscles Common to both Lips are such as are Inserted into the Angles of the Mouth, as the Zugo­maticus, Elevator, Depressor, and Con­strictor Labiorum.

Zugomaticus.

So called by Riolan because it arisesAnthro­pog. Lib. v. Cap. 12. from the Os Iugale or Zugoma (9).Fig. xvii. Its Origination is Round and Fleshy from the External part of the said Bone, whence Descending Obliquely Forwards is Inserted near the Angle of the Lips. (G.)Fig. i.

When this Muscle and its Partner Act, they draw both Lips upwards, and make a Pleasant Countenance.

Elevator Labiorum.

This lies between the Former Muscle and Elevator Labii Superioris Proprius. It Ariseth from the Os Quar­tum of the Upper Jaw (5), and De­scendsFig xvii. Directly to its Insertion under the Termination of the Former. (D.)Fig. i.

Depressor Labiorum.

This Arises Fleshy from the Lower Edge of the Inferior Jaw Bone (10)Fig. xvii. laterally, and Ascends Directly to its Insertion at the Angle of the Lips. (H.)Fig. i.

This with its Partner and the Qua­drati Acting express a sorrowful Coun­tenance, in drawing down the Corners of the Mouth and Cheeks.

Constrictor Labiorum it. Sphincter, & Orbicularis Labiorum.

This environs the Lips with Orbi­cular Fibres, and when it Acts it Pur­ses them, wherefore some name it Os­culatorius. (F F.)Fig. i.

[Page 62]The Muscles Proper to the Upper or Nether Lip in particular are three Pair, (viz.) Elevatores Labii superioris; De­pressores and Elevatores Labii Inferioris: Of these in Their Order.

Elevator Labii Superioris.

This Arises Fleshy from the Fore­part of the Os Quartum of the UpperFig. xvii. Jaw (5) immediately above the Ele­vator treated of before, and descends obliquely under the skin of the Up­per Lip, joining with its Partner in a Middle Line, from the Septum Nari­um to its Termination in the Sphincter Labiorum. (EE.)Fig. i.

Depressor Labii Inferioris.

Its difficult to determine whether This be One only or Two Muscles. It lying between the Depressores Labio­rum Communes (described above) pos­sesses that part of the Lower Jaw called the Chin (10), and AscendingFig. xvii. with a direct and transverse order of Fibres is Inserted into the Nether Lip,Fig. i. [...] Fig. iv. G. G. in Depressing of which it Turns it Out­wards. (I.)

Elevator Labii Inferioris.

This Muscle with its Partner lies within the Lower Lip. These We First Observed some time since, They Arise Fleshy from the Inferior Part of the Gums of the Lower Jaw, which belong to the Dentes Incisorii, and Descend Directly to their Implanta­tions in the Inferior part of the Skin of the Chin (FF); hence it is whenFig. iv. These Act they make divers Indenta­tions in the Chin, as may be Ob­served in Living Persons when the Lower Lip is drawn upwards.

Attollens Auriculam.

This consists of divers Fleshy Fibres, and is annext to that part of the Pe­ricranium that covers the Temporal Muscle, whence it Descends Directly to its Implantation at the superior part of the second Wrinkle of the Cartilage of the Ear. (M.)Fig. i.

Its Name declares its Use.

Retrahens Auriculam.

By some called Triceps Auris, be­cause it has sometimes Three Begin­nings. M. Du Verney says it is com­posedDe l'Org. Del'Ovie. of Five or Six Fleshy Fibres which have their Origination from the superior and Forepart of the Apo­physis Mastoides, and Descend obliquely to their Insertion in the middle of the Concha Auriculae.

[Page 65]N. These Muscles of the Internal Ear cannot be Demonstrated till after those of the Head are dispatcht, and the Brain removed; but we shall follow the example of others, and insert their Descriptions in this place; it being also customary in the Myological Lectures at Chirurgeons Hall to shew them in a dried Preparation from the precedent Subject.

Externus Auris vel Laxator Externus.

This lies in the Upper Part of the Meatus Auditorius, having a short Fleshy Body with a long slender Ten­don. It Arises from the External and Superior Margin of the Meatus Audi­torius, soon becoming a slender Ten­don passes directly to the Upper part of the Membrana Timpani, on which it Descends for some space to its Inser­tion in the long Process of the Malleus, where it is Contiguous to the said Membrane. This draws the Mana­brium of the Malleus, together with the Membrana Timpani Forwards.

Obliquus Auris.

This may be also called Semicircu­laris from its Position it lying in the [Page 69] External Parts of the Bony Channel of the Aquaeduct, whence marching somewhat Upwards and Backwards, it enters the Timpanum in a very oblique Sinuosity Excavated immediately a­bove the Bone where the Timpanum is Inchased, and is Inserted to the slen­der Process of the Malleus. The Sin­uosity in which this Muscle passes is that which may be taken notice of in the Upper Part of the Bony Circle of the Faetus. This we don't find De­scrib'd any-where before Du Verny.

Internus Auris.

This lies in a Bony Channel Exca­vated in the Os Petrosum, which makes one of the Parietes Timpani; one part of this Channel is without the Tim­panum, and lies in the upper part of the Bony Passage which goes from the Ear to the Palate; the other Part which is within the Timpanum, advan­cing as far as the Fenestra Ovalis, makes in that Place a Rising, upon which, as on a Pully, the Tendon of this Muscle passes to the other side of the Timpanum, and Inserts it self at the Posterior Part of the Handle of the [Page 70] Malleus a little below the Insertion of the External Muscle; by which means it draws it towards the Os Petrosum. The Origin of this Muscle is Precisely in that Place where the Bony part of the Aquaeduct Terminates. It is co­vered with a Nervous Coat which forms a Sheath, accompanying it in its whole progress, and binding it fast to the Channel. When this Muscle Acts it pulls the Manubrium of the Malleus towards the Os Petrosum, where­by the Membrana Timpani becomes somewhat Concave outwardly.

In the Tendon of this Muscle in some Animals Schelhamar has some­timesChap. iii. Sect. iv. Observed a small Bone, which we suspect he mistook for the Muscu­lus Stapidis, in which Tendon, my very good Friend, Dr. Adair, an Ac­curate Anatomist, lately communi­cated his Observation of it to me, as it appear'd in a Calfs Head, which at first sight may deceive the Enquirer, it being annext to the Stapes, and in Figure like the Osculum Quartum of Sylvius; but if you be careful in your Examination, you may find both in the same Organ; the latter common­ly remaining on the long Process of [Page 71] the Incus when separated: but if if you leave the Stapes (C) in Situ, Fix. ix. you may see in that Animal, the Ori­gin, (E) Progress (F) & Insertion (C) of its Muscle, together with the Bone in its Tendon (F) as it passes over a Pro­jection of the Os Petrosum, which com­poses the Foramen Rotundum (B) on which we suspect the Tendon of this Muscle Acts, as on a Trochlea, to which end that small Bone is placed, not unlike the Petella of the Knee and Ossa Sesamoidea of the Feet; which is an elegant Mechanism in Nature.

Musculus Stapidis.

This lies hid in a Bony Pipe, ex­cavated in the Os Petrosum, almost at the Bottom of the Timpanum, whence it takes its Origin. It's Belly is big and Fleshy, and suddenly forming a very thin Tendon, which Descends to its Insertion at the Head of the Stapes. The Pipe, which contains the Belly of this Muscle, is about the sixth part of an Inch long, and is much larger then the Foramen, through which its Tendon Passes.

[Page 72]When this Acts, it draws the Stapes upwards to the Foramen Ovale.

The Order of Dissection obliges us to Examine the Muscles of the Os Hyoides next, to which end the Mastoidei must be raised on both sides of the Neck; the one being Freed from its Origination, and left at its Insertion; the other on the contrary may be raised from its Insertion, and left at its Origin. This done, the Biventral Muscles of the Lower Iaw may be observed in their whole Progress, where­in may be Noted, that They Descend from their Originisations through the Stylohy­oides to the Os Hyoides, where an An­nulus is made on each side for the Trans­mission of their middle Tendons; after which They reascend to their Implanta­tions. These being also Raised contrary­wise like the above-mentioned Mastoidei, and the Perforations of the Stylohoidei enlarged, thorow which each contrary end of These must be drawn, leaving the one at its Origination, and the other at its Insertion, till we come to Describe the rest of the Muscles which move the Lower Iaw.

Sternohyoideus.

This does not Arise from the Upper part of the Sternum (31), as Anato­mistsFig xvii. generally write, but from the [Page 74] Internal part of the Clavicula (14) nextFig. xvii it, where its Origination is Broad and Fleshy, and Ascends directly over the Sternothyreoideus and Larynx, of an equal Breadth and Thickness, to its Insertion at the Basis of the Fore Bone of the Os Hyoides. (S. S.)Fig. i.

This with its Partner Acting, pulls the Os Hyoides, together with the Tongue and Larynx, directly down­wards.

Coracohyoideus.

This does not Arise from the Pro­cessus Coracoides Scapulae (16), as VulgarFig. xvii Anatomists pretend It's Origination being Round and Fleshy from the su­perior Costa of the Scapula, at the root of the said Process, whence, marching Obliquely under the Mastoideus, it be­comes Tendinous, but growing Fleshy again, It's Inserted into the Basis of the Fore Bone of the Hyois, near the Implantation of the Former Muscle. (T. T.)Fig. i.

This running under the Mastoideus as on a Trochlea, it there becomes Tendinous, not unlike the Digastricus of the Lower Jaw, wherefore, This [Page 75] by some is also Called Biventer. When It Acts together with Its Partner, They do not only assist the Former in drawing the Os Hyoides, Tongue and Larynx, downwards; but, They also pull them somewhat Inwards, towards the Vertebrae of the Neck.

Stylohyoideus.

By some called Styloceratohyoideus, because its said to be Inserted to the Horns of the Os Hyoides. It Arises sharp and Fleshy from the Processus Styloides (f), and soon growing lar­ger,Fig. iii. It Descends obliquely Forwards to the Os Hyoides, in half its Progress thither, its Fleshy Body is Divided, to give way to the Transmission of the Middle Tendon of the Digastricus of the Lower Jaw. This Muscle is well exprest (in situ) by Bidloo.

This with its Companions, the Sty­loglossus and Stylopharyngoeus Acting on each side, do draw up the Os Hyoides, Tongue and Larynx, together with the Fauces in Deglutition; whereby the Masticated Aliment is not only Comprest into the Latter, (they be­ing then Dilated) but the Epiglottis is [Page 76] Deprest, and adequately covers the Rimula of the Larynx by its Aproxi­mation to it, by which means the Descent of the least Part of the Aliment into the Aspera Arteria is Hindered; which Mechanism in Nature is indeed very Admirable.

Mylohyoideus.

Though Falloppius and his FollowersDissertat. Anatom. make this a Pair of Muscles, It seems not to be divisible without apparent Violence. It possesses all that space which is between the Lower Jaw and Os Hyoides; Arising Fleshy from both sides the Mandible (10) Inter­nallyFig. xvii. near the Dentes Molares (A),Fig. iii. whence Marching with a double or­der of Fleshy Fibres, the outward­most of which pass directly to their Implantation in the Os Hyoides; and the Middle run Transversly over the following Muscles, being inseparably joined to each other with a Middle Line, as is well exprest by Bidloo. T. 15.

Besides the Uses commonly ascribed to this Muscle in moving the Os Hy­oides Tongue, and Larynx, Upwards and Forwards, and to either side; its [Page 77] last Described Transverse Order of Fibres have still a further Use in Com­pressing the Glandulae Sublinguales who lie immediately under them on each side: whereby they Hasten the Egress of the Spittle from the Inferior Salival Ducts into the Mouth. Hence it is we imploy these Muscles (as in the Action of Deglutition) when we want Saliva to moisten the Mouth: And in that Action also they supply it with fresh Saliva to join with those Ali­ments where Mastication is not re­quired; which Artifice of Nature de­serves our Admiration.

Geniohyoideus.

This with its Partner are Short, Thick, and Fleshy Muscles, Arising from the Internal parts of the Lower Jaw-Bone called the Chin (A), andFig. iii. Dilating themselves, are soon lessened again, and Inserted to the superior part of the Fore-Bone of the Os Hyoides.

These Acting pull the Os Hyoides, &c. both Upwards and Forwards, and assist the Genioglossi in thrusting the Tongue out of the Mouth; of which in the following Chapter.

[Page 78] All these Muscles of the Os Hyoides being raised from their Originations, and left at their Insertions, the whole Bone to­gether with them may be taken out; by dividing its two extreams from the Two Processes of the Scutiformal Cartilage, and cutting off the Originations of the Cera­toglossi and Hyothyroeidei, (of which hereafter). This done they may be ex­panded on a Plain, as they are repre­sented by Placentinus and VeslingiusCasser. Lib. ii. Syntag. Anatom. Cap. xi. in their Figures; the latter of which calls the last Described Geneiohyoides, and the preceding Geneiohyoides par internum.

Genioglossus.

This with its Partner lies immedi­ately under the Described Geniohyoidei. They Arise Fleshy from the Fore-part of the Lower Jaw Internally (A), andFig. iii. inlarging themselves, are inserted to the root of the Tongue. (DD.)Fig. v.

When these Act they pull the Tongue Forwards, and Thrust it out of the Mouth.

Ceratoglossus.

This we cut from its Broad Fleshy Origination at the superior part of the Os Hyoides laterally, whence it Ascends to its Insertion at the Root of the Tongue. (C C.)Fig. v.

This with its Partner Acting draw the Tongue into the Mouth directly; if One of them Acts only, it moves it to one side.

Styloglossus.

This Arises Sharp and Fleshy from the Processus Styloides (f), whenceFig. iii. Descending Obliquely Forwards its Inserted to the root of the Tongue immediately below the Implantation of the Former. (E E.)Fig. v.

This Pulls the Tongue Up and In­wards in the Action of Deglutition, as before noted.

To these most Authors except Fal­loppius ☞ add the Basioglossus, by some called Hypsiloglossus, Arising from the Os Hyoides, and Inserted to the Tongue, but whether there be such a Muscle our late Enquirers have not acquainted Us.

Sternothyroideus.Bid. T. 15. F. i. H H.

This Arises Broad and Fleshy from the Upper and Internal part of the Sternum, (31) whence Ascending on theFig xvii. sides of the Wind-pipe over the Glan­dulae Thyroidei, it's Inserted to the In­ferior part of the Thyroidal or Scu­tiformal Cartilage. This with its Partner Pulls the Larynx Downwards, and lengthens the Canalis or Distance between the Rimula and Tip of the Tongue, (which latter we take to be the true Plectrum Vocis) whereby the Tone of the Voice is rendred Grave.

Hyothyroideus.H [...]eron. Fab. ab Aquapen. De Lary. F. 23. n. 34. N.

This Arises Fleshy from the inferior part of the Os Hyoides laterally, op­posite to the Origination of the Cera­toglossus, and Descends directly to the lower part of the Scutiformal Carti­lage near the Implantation of the Former.

This with its Fellow draw the La­rynx upwards in an Acute Tone of the Voice; the Canale of the Aspera Arteria being also streightened thereby.

[Page 83]We proceed next to the Proper Muscles of the Larynx.

In the Administration of These, the Musculus Oesophagioeus must be freed from both sides the Scutiformal Cartilage, and the Arytenoidal Cartilages divided from the Glottis, and the Aspera Arteria also separated from the Gula: Cut off the Former near the Bronchia, and the Dissection of the subsequent Muscles will be the better performed.

Cricothyroideus.Idem. F. 26. R R.

This is seated on the Forepart of the Larynx, and is a Short Thin Fleshy Muscle: Arising from the Forepart of the Cricoides, whence marching ob­liquely, is soon Inserted to the Scuti­formis internally laterally.

This by De Musc. Cap. xii. Galen and Lib. ii. Cap. xxi. Vesalius is made Two Muscles; but in separating the Inferior processes of the Scutiformal Cartilage from the Anularis, you will find but One on each side, says Aqua­pendente: Fabrit. De Laryn. C. viii. The Origination and Inser­tion of which is supposed by some to be e contrario, and that its Use is rather to pull up the Anularis than to bring [Page 84] down the Scutiformis nearer it; but the Controversy (we think) is of no moment, since all Muscles move the Parts less Stable to those more Fixt, as is Instanced in the Recti Abdominis after Spigelius. Chap. i. pag. 26.

Cricoarytaenoideus posticus.Aquapen­den. F. 25. S S. 38. S.

This lies on the back part of the Larynx, and is of a quadrangular Fi­gure. It Arises from the Posterior part of the Anular Cartilage, filling a shallow depresure of it with Fibres ascending Obliquely outwards, to their Insertion at the lowermost part of the Arytenoidal Cartilage.

This with its Partner serve for the Apertion of the Rimula; which will plainly appear, if with your Knife you repress this Muscle, the Arytae­noidal Cartilage will then be opened thereby.

Cricoarytaenoides lateralis.Id. F. 24. 32. 33. V.

This is a small, short, Fleshy Muscle, Arising from the Cartilago Cricoides la­terally, and Ascending obliquely is Inserted to the Arytenoidal Cartilage [Page 85] near the Implantation of the Former Muscle.

This pulls the Arytaenois sideways, and thereby opens the Rimula.

Thyroarytaenoideus.Aquapen. 24. M. 32. 33. xxx.

This is the largest of all the Pro­per Muscles of the Larynx. It Aris­eth together with its Partner in the Internal and Concave part of the Scu­tiformal Cartilage, from whence they Ascend to their Implantations at the Foreparts of the Arytaenoides.

When these Act, they approach the Cartilages to which they are Fixed, and shut the Rimula. The Contracti­on of these Muscles through an In­flamation in an Angina will bring sud­den Death, which Case I remember I heard the late Dr. Croon say he had once Observed in Dissection.

Arytaenoideus.Id. F. 25. 38. T.

This is the smallest Muscle belong­ing to the Larynx, it's in the Opinion of some Double, but has always ap­peared to us Single. It Arises from the External part of one of the Ary­tenoidal [Page 86] Cartilages, and running Transversly, is Inserted to the other.

This pulls the Arytenoidal Carti­lages nearer each other, and shuts the Rimula Adequately.

The Opinion of Dr. Croon (as it's related by Dr. Gibson) concerning theBook v. Chap. xi. Use of these Muscles, we can by no means Approve.

Stylopharyngeus.

This has a Round, Sharp, and Fleshy Origination at the root of the Processus Styloides, (with the above treated Styloglossus) whence descending oblique­ly, it expands it self at its Termina­tion on the Internal Glandulous Mem­brane of the Fauces, in the middle of which its joined with its Partner. (AA.)Fig. vi.

These Acting draw the Fauces up­wards, and Dilate Them in order to receive the Masticated Aliment in Deglutition.

These being Cut from their Origi­nations, the next that offer themselves to the Knife are those which fasten this Part to the Basis of the Cranium, which according to Riolan and othersAnthrop. Lib. v. Cap. xix. consist of Two Pair of Muscles; but to us rather seem to be but one Muscle [Page 88] with Two Fleshy Beginnings spring­ing from the Processus Pterigoidei, where­fore we Call it Pterigopharyngeus.

Pterigopharyngeus.

This Arises Thin and Fleshy from both Pterigoidal processes of the Os Cuneiforme, also from the Root of the Tongue and extremities of the Os Hyoides; from these Places its Fleshy Fibres run in a semicircular manner, embracing the superior and Back part of the Glandulous Membrane of the Fauces, where they meet in a middle line. (B B.)Fig. vi.

When this Muscle Acts it brings the Middle or Back part of the Faucés towards a Plain, by which means, the Tonsils, together with the rest of the Glandules, are Comprest in the Evacuation of their Mucus, to join with the Aliment in its Descent into the Stomach in Deglutition. And at other times to promote Screation, in which This Muscle is the chief In­strument; That the Tonsilae approach towards each other, is Observable when we Inspect these Parts in living Persons.

Oesophageaeus seu Sphincter Gulae.

This seems to be a continuation of the Former; Arising from each side the Scutiformal Cartilage, and like it passes to a Middle line on the Back part of the Fauces. (C. C.)Fig. vi.

This does not only assist the Former in Compressing the Masticated Ali­ment into the Gula, but is thought by some to streighten the Scutiformis, and render the Tone of the Voice more Acute.

To these may be added the Perfo­rated Muscle of the Gula, as Dr. Willis calls it.

Vuginalis Gulae.

Steno supposes this to consist of a double order of spiral Fibres mutual­ly intercussating each other. Dr. Wil­lis Pharma. Rational. Cap. ii. Sect. ii. says the whole Oesophagus seems to consist of Two Muscles, which make Four Parallelograms with their oppo­site Fibres decussating each other. But in Man we find it far otherwise, in whom the Fibres of this Muscle are Longitudinal, and Oblique; the For­mer [Page 90] seem to take their Original at the Arytenoidal Cartilages, and pas­sing somewhat Obliquely to the Back part of the Oesophagus (BB),Fig. vii. descend to the Stomach: The Latter (AA) seem to be a continuation of the last treated of Muscles, descending obliquely in a spiral manner not un­likeDissertat. in Lib. de Febribus intermit­tentibus. those of the Intestines Described by the Learned Dr. Cole.

Sphaenopalatinus. [...]slingius Tab. Cap. xi. b b.

This descends from a Round Fleshy Origination at a Process of the Os Sphaenoides (X), which is in a DirectFig. iii. Line between the Ala Vespertilionis (P), and Processus Styloides (f), becoming a Round Fleshy Belly, in half its Pro­gress grows less again near its lateral Insertion to the Posterior part of the Gargareon.

This with its Partner Acting Draw the Gargareon with the Vuula Upwards and Backwards; which hinders the Masticated Aliment from Regurgitate­ing through the Foramina Narium in Deglutition.

Pterigopalatinus seu Sphaenopterigopalati­nus. [...]bid. c c.

The Former Appellation intimating its Progress and Insertion; the Latter its Origin also. This Arises from the same Process of the Os Sphaenoides, as the Preceding Muscle, and like it, [Page 92] Descends according to the length of the Interstice made by the Internal Ala of the Os Sphaenoides and Musculus Pterigoideus Internus (B) of the LowerFig. iii. Jaw; and becoming Tendinous, mar­ches over the Processus Pterigoides, and is Inserted to the Forepart of the Gar­gareon.

The Tendon of This, passes over the Pterigoidal Process, which like a Pully gives It a Different Power from that of the Former Muscle, though they have both their Origin from the same Place. Wherefore, contrary to the Preceding. This Draws the Gar­gareon Forwards and Downwards; which Contrivance in Nature is no less remarkable than any of those where the like Artifice of a Trochlea is made Use of.

N. Now all the Muscles of the Lower Iaw may be Dissected; its Depressors be­ing left at Their respective Originations and Insertions, as before, Chap. XII. Page 72.

Temporalis it. Crotaphites. Fig. i. L.

This has a large Semicircular Fleshy Beginning, from part of the Os Frontis (2), Syncipitis (1), Sphae­noides, Fig. xvii. and Temporalis (3), from these places its Fibres pass (like Lines drawn from a Circumference to a Center) under the Os Iugale (9), from whence also Arise some Fleshy Fibres joining with the Former at their United, partly Tendinous and partly Fleshy Insertion, to the Upper part of theFig. iv. Processus Corone of the Lower Jaw. (B.)

[Page 94]This with its Partner draws the Lower Jaw upwards. We could ne­ver Observe those Dreadful Symptoms Authors Relate in Wounds of this Muscle, though part of it has been Divided to Apply the Trepan in Fra­ctures of the Cranium.

Masseter.

This is a short, Thick, partly Fleshy, and partly Tendinous Muscle; A­rising Forwards from the Os Primum Maxillae superioris (6) Backwards fromFig. xvii. the Os Iugale (9), from hence De­scending (with Fibres, decussating each other in Acute Angles) is Inserted to the Inferior and External part of the Lower Jaw Bone.

This Assists the Former in its Of­fice. The Ductus Salivalis Superior pas­sing over this Muscle, is a Pro­vident Contrivance in Nature to Ac­cellerate the Motion of Saliva in Mastication. The next which offers it self to our Consideration is the Di­gastricus, by some called Graphoi [...]s, imagining it to Arise from the Styloi­dal Process.

Digastricus seu Biventer. [...]id. T. [...]5. F. i. [...]BB.

So called from its peculiar confor­mation, having Two Bellies. It A­rises Fleshy from the Forepart of the Processus Mastoides (8), whence De­scendingFig. xviii. Fig. iii. G. it becomes Tendinous, pas­sing through the Stylohoideus and an Annular Ligament laterally fastned to the Os Hyoides; from which Bone some Tendinous Fibres do Arise and join with its Second Fleshy Belly, A­scending from thence to its Insertion at the Middle of the Inferior part of the Lower Jaw. The Middle Tendon of this Muscle and its Partner passing through Two Annular Ligaments Fixt to the Os Hyoides, as Ropes through a Dou­ble Pully is a Wonderful contrivance of the Author of Nature to render them capable of Pulling the Lower Jaw Down, which had their Progress been Direct from their Originations, they could not have performed. Nor is there any Processes whether of the Vertebrae of the Neck, or the Neigh­bouring Parts, that could give an Ori­gination to these Muscles, below their Insertions, as in some Quadrupeds; [Page 96] Wherefore the Divine Architect of Human Bodies has placed this Double Pully below their Terminations, whereby they Perform their designed Office. Hence Deglutition is hinder­ed, when these Muscles are in action, they then preventing the Ascent of the Tongue and Larynx. Neither can we at that time draw the Lower Jaw down because the Center of di­rection is pulled upwards. Where­fore we are obliged on that occasion to keep the Jaws close together. But in Dogs and other Voracious Animals who have these Muscles Arising from the Transverse Processes of the First Vertebra of the Neck, these Actions are not Dependent; whence it is they devour their Aliment so Quick.

Pterigoideus Internus.

So called from its Origin and Si­tuation. It Arises partly Tendinous and partly Fleshy from the Processus Pterygoides or Aliformis of the Os Sphae­noides, whence it Descends to its Im­plantation at the Internal and Inferior part of the Lower Jaw Opposite to the Termination of the Masseter. (B.)Fig. iii▪

[Page 97]Either of these Acting draws the Jaw to the Contrary side, if Both Act they assist the Temporales and Masse­teres.

N. To discover the Following Muscle the Two last Named on either side must be removed. But if you still desire a fairer Prospect of it, with a Chissel Cut off part of the Processus Corone, toge­ther with the Os Jugale.

Pterigoideus Externus.

This like the Former receives its Name from its Situation and Origin: It Arising from the External Part of the said Processus Pterigoides, (P) and supe­riorFig. iii▪ part of the Os Sphaenoides (C) seated in the cavity of the Temples opposite to the Os Iugale (9), and runs Back­wardsFig. xvii. to its Insertion at the Neck ofFig. iii. E. Fig. iv. the Processus Condyloides (AA) of the Lower Jaw.

When This and its Partner Act, They draw the Lower Jaw Forwards; and Force the Teeth of the Inferior Jaw beyond those of the Superior, as Falloppius their first Describer observes.Observat. Anatom.

Intercostales externi & Interni.

These are placed in the Intervals of the Ribs as their Names Declare. Their Number on each side is Twice Eleven, equal to the Number of the Interstices in which they are lodged. Their Originations are differently as­signed by Anatomists, but we shall acquiesce in the Opinion of Dr. Muyow (after Steno) who thinks both (viz.) Intercostales Externi, and Interni, do Arise from the Lower Edge of each Superior Rib, and are inserted to the Upper edge of each Inferior one. These are Thin and Fleshy; the Fibres of the External pass from above Obliquely downwards to the Forepart or Ossa Pubis (38): Those of the Internal,Fig. xvii▪ descend in like manner obliquely to­wards the Back-part or Os Sacrum (O):Fig. xvii▪ Their Fibres Decussating each other like the Letter X.

The Sternum being raised by dividing its Cartilages on each side from the Bony endings of the Ribs, the following Muscle will appear underneath.

Triangularis.

This with its Partner lies on each side the Cartilago Ensiformis (32) with­inFig. xvii. the Cavity of the Thorax under the Sternum (I); some times this appears toFig. xviii. be Three, at other times Four distinct Muscles on each side. It Arises from the Inferior part of the Os Pectoris, whence its Upper part Ascends, and Lower Descends to its Implantations at the Bony endings of the Fourth, Fifth, Sixth, and sometimes Seventh, and Eighth Ribs, near their Conjuncti­ons with their Cartilages.

Its reputed Use by most (if not all) Anatomists, is to Contract the Breast.

The second Order of Muscles (viz.) such which move the Thorax in Com­mon with the Contiguous Parts to which They are affixt; Comprehends the three Scaleni, two Serrati Antici, Sabclavius, and Diaphragma.

Scalenus primus.

This Arises Fleshy from the Fore­part of the Second, Third, and Fourth Transverse Processes of the Vertebrae [Page 102] of the Neck (n n); and DescendingFig. xviii. Obliquely Forwards, becomes Ten­dinous at its Insertion to the First Rib (i); The Axiliary Nerves passFig. xvii. between This and the Following Muscle.

Its Use is to draw the superior Rib together with the rest Upwards in In­spiration.

Scalenus Secundus.

This springs Fleshy from the Se­cond, Third, Fourth and Fifth Trans­verse Processes of the Vertebrae of the Neck (n n), laterally (like the Former);Fig. xviii. in its Descent it becomes Thin, and Ten­dinous, marching over the First Rib to its Insertion in the Second and some­times to the Third.

Scalenus Tertius.

This has its Beginning near the Former, from the same Transverse Processes of the Vertebrae of the Neck; as also from the Fifth and Sixth of those Processes, and is soon Inserted to the First Rib.

[Page 103]These Three last Treated of Muscles are called Scaleni from their Figure, having three unequal sides. Though they are most commonly Enumerated and Described among those of the Neck, to whose Motion they are sub­servient, yet the Judicious Falloppius Observat. Anatom. duely considering the Subclavius and Serratus Superior Posticus to be insuffi­cient for the Elevation of the Chest, assigns These part of that Office.

Subclavius.

This next presents it self to the Knife. It Arises Fleshy from the In­ferior part of half the Clavicula (14),Fig. xvii. next its connection with the Spina Scapulae (15), hence its Fibres Descend Obliquely Forwards to its Insertion at the superior part of the First Rib (i) near the Sternum. Its Use is intimat­ed above; but Spigelius who has writ­tenLib. iv. Cap. ix. a Chapter expressly about this Muscle, pretends it Depresses the Cla­vicula, for which Opinion he Argues strenuously, and to this purpose re­lates an Observation from Hippocrates, that when the Clavicula is Fractured near the Sternum that next part visibly [Page 104] Ascends, and that part next the Sca­pula, together with the Humerus, falls down; but if it's Fractured near the Scapula, then neither part Rises; which, as our Author not absurdly Conje­ctures, to depend on the Terminati­on of this Muscle. In the first Case, it draws the Clavicula, together with the Humerus downwards, the Fracture being betwixt its Insertion and the contrary end of the Bone that is fixt to the Sternum. In the Latter, it be­ing Fractured on that part where its Inserted it may draw the ends of the Bone nearer each other.

Serratus Minor Anticus.

Anatomists generally reckon this Muscle amongst those of the Scapula; but we are persuaded from its Position that it may be equally serviceable to the Thorax, in Elevating those Ribs it is Inserted to: Wherefore we offer it Indifferently, whether belonging to one, or the other; but chuse to Insert it in this place, because it now appears in Situ. If due Care be not taken in raising the Pectoralis, you will be in danger of Wounding this. It Arises [Page 105] Fleshy from the Processus Coracoides Scapulae (16), and Descends ObliquelyFig. xvii. Forwards, becoming Broader and Thinner, and is Inserted Fleshy to the Bony part of the Second (k), Third (l), Fourth (m), and Fifth Ribs (n). If the Scapulae are Elevated by their Pro­per Muscles, This with its Partner are then capable of Dilating the Breast in Large Inspirations. But if they are Deprest, it may be easily conceived with what Difficulty that Action must then be Performed.

Serratus Major Anticus.

This Arises Fleshy from the whole Basis Scapulae, and Passing under the Subscapularis it becomes Broader and Thicker, still running somewhat For­wards till its Inserted to the Eight su­perior Ribs laterally (i k l m n o p q)Fig. xvii. by so many Distinct Fleshy portions or Digituli, representing the Teeth of of a Saw; The Two and sometimes Three Inferior of which are Indented with the Obliquus Descendens of the Abdomen, as was before noted. This like the Former Dilates the Thorax, or Moves the Scapulae Forwards and [Page 106] Downwards when its Muscles are relaxt.

The next Muscle belonging to the Thorax, and appears as the Body lies Supine, is the Diaphragm. We shall not here enumerate the many Names bestowed on this Part, our Task be­ing only at Present to consider it as a singular Muscle elegantly Framed for those Uses for which the Author of Nature has design'd it.

Diaphragma.

Specim. Myologiae. Steno supposes this to be a Di­gastric Muscle. Diaphr. Structur. Cap. ii. Caspar Bartholin conceiving it Double, calls the Lower part springing from the Vertebrae of the Back and Loins the Musculus Infe­rior, and the Opposite Arising from the Cartilaginous Endings of the Ribs, the Superior: or Imagines it Trigastri­cal, as above noted Chap. I. Which latter Opinion of his seems to qua­drate to this Part in Birds. But whe­ther we may suppose it One or Two Muscles in Man, is a matter more of Controversy then Use. Its Inferior part Arises partly Tendinous and part­ly Fleshy on the Right, from the [Page 107] First (u), Second (w) and Third Ver­tebrae Fig. xvii. of the Loins (x); on the Left from the Last, and Last but one of the Back, hence Ascending with Fleshy Fibres on each side running Streight, but in the middle pass somewhat Curvedly, intersecting each other do as it were embrace the Oesophagus, after which they become Tendinous, and join with its Upper part, which Arises Thin and Membranous, but soon grows Fleshy at the whole Inferior Margin of the Cartilaginous endings of the Ribs, and lower part of the Os Pectoris; whence, its Fleshy Fibres like Lines drawn from a Circumfe­rence towards a Center, pass to its Middle part, where its Tendinous Fibres are Intercussated with each other, and exhibit a Rete. It has Two large Perforations, the One in its Tendinous part to Transmit the Vena Cava towards the Right Auricle of the Heart; the other in its Fleshy part, which like an Anulus embraces the Oesophagus (as above noted). Its double Origin at the Vertebrae (34)Fig. xvii. gives way to the Descending Trunck of the Arteria Magna, and Two As­cending of the Ductus Chyliferus and Vena Azygos.

[Page 108]Its Use in the Animal Oeconomy is too Large to be Inserted in this place. Pecquet observes when all the Muscles of Respiration are separated and re­moved, the Diaphragma and Interco­stales excepted, the Animal still per­sists to Breath. When we Inspire, its superior surface comes towards a Plain. In Expiration it's Convext towards the Thorax, and Concave towards the Abdomen. In the Former the Viscera of the Lower Belly are Comprest, and the Cavity of the Thorax enlarged. In the Latter the Air is exprest out of the Vesciculae of the Lungs.

We might here Insert another sin­gular Muscle the Heart, but it not being an Instrument of Voluntary Motion, or moving any other Part besides it self and the Blood, we shall therefore leave it, being sufficiently sensible how Accurately Dr. Lower, Vieusenius, and Others have Described and represented it in their Figures. The rest of the Muscles that appear on the Body lying Supine, do partly belong to the Head, Neck, and Limbs, of which in their Proper Or­der.

[Page 109]N. To Prosecute our Work We must now lay the Subject in a Prone Position the Back Uppermost, continuing our Section from the Occiput down to the Os Sacrum, Intersecting it with a Trans­verse Line over the Regio Lumbalis. Which done, and the Common Integu­ments removed, the Subjacent Muscles may be best Dissected in the following Order.

Cucullaris, & Trapezius.

So named because this with its Fel­low covering the Back Represents a Cowl. It Arises Fleshy from the Os Fig. xviii. Occipitis (2), Tendinous from the Li­gamentum Colli, and Apex of the Spine of the last Vertebra of the Neck (f), [Page 106] [...] [Page 107] [...] [Page 108] [...] [Page 109] [...] [Page 110] and Eight superior of the Thorax (PP),Fig. xviii. from which Broad Origination be­coming Thick and Fleshy, its so In­serted to the Clavicula (11), and Ten­dinous to the Spina Scapulae (16), Each Muscle is Triangular, and both conjointly compose a Lozenge or Tra­pezium, whose large Diameter extends from the Occiput to the Fifteenth Ver­tebra; the shorter from near the Ex­tremity of the Spina Scapuloe on one side, to that of the other. They contain a Triple Series of Fibres; the Middle passing directly Transverse from the First Vertebra of the Thorax: those Above Descend, and those be­neath Ascend to their Insertion; whereby the Scapula is variously moved according to their Directions, either Obliquely Upward, Directly Back, or Obliquely Downwards.

N. You must proceed with Caution in the separation of this Muscle, least you Raise the following with it, which adheres very strictly to its Tendinous part, where it springs from the Superiour Spines of the Vertebrae Thoracis.

Rhomboides.

So called from its Figure. It lies immediately under the Former, in some Subjects we have found it divi­ded into Two distinct Muscles on each side, which Bidloo also observes. It Arises Tendinous from the Two Inferiour Spines of the Vertebrae of the Neck (e f), and Four Superior of theFi. xviii. Thorax (PP), whence descending Ob­liquely, becomes Thick and Fleshy, and is so Inserted to the whole Basis Scapulae (13, 13).

When it Acts, it draws the Scapu­la Upwards and Backwards.

N. This adheres strictly to its Subjacent Muscle the Serratus Superior Posticus, wherefore you must be cautious in Raising it.

Levator Scapulae.

By some called Levator Patientiae, because we make use of it in large Inspirations, in order to Expire, as when we Sigh, (as they call it.) This lies immediately under the Cucullaris, arising by so many separate Origina­tions from the Second, Third, Fourth, [Page 112] and Fifth Transverse Processes of theFi. xviii. Vertebrae of the Neck (nn), which uniting into one large Fleshy Body, Descends Obliquely to its Insertion at the Superior Angle of the Scapula (13). Its Name declares its Office.

N. We proceed next to the Muscles of the Thorax which appear on the Backside, the Body lying Prone; to discover which, the Latissimus Dorsi must be removed, part of it being raised in the Ilia in Dissecting the Muscles of the Abdomen, where you must pursue its Separation, first Cutting it from the Posteriour part of the Spine of the Ilium (30), separating it (if possible) from the Serratus Inferior Po­sticus; Freeing it from the Spines of the Loins (RR), and Inferiour of the Tho [...]ax (PP), and leave it at its Inser­tion to the Os Humeri (19). This done on both sides, the rest of the Muscles of Respiration offer themselves.

Serratus superior posticus.

This lies immediately under the Rhomboides, as above noted. It Arises with a Thin Tendon from the Two Inferior Spines of the Vertebrae of theFig. xviii. Neck (f g), and Three superior of the Thorax (PP), from thence Descend­ing Obliquely over the Splenius Capitis, and Upper Parts of the Sacrolumbalis, and Dorsi Longissimus, it becomes Fleshy, marching under the Scapula to its Insertion at the Curvature of the Second (i), Third (k), and Fourth Ribs (l), by so many distinct Fleshy Endings, Representing the Teeth of a Saw.

[Page 114]This assists in Elevating the Ribs or Thorax.

Serratus inferior posticus.

The Origination of this Muscle is much Larger than Authors generally assign it; In a Robust Subject we Ob­served its Continuation not only from the Spines of the Vertebrae of the Loins (RR), but from all those of theFig. xviii. Thorax (PP), as well underneath as below the Former Muscle; its Supe­rior and Inferior Parts being entirely Tendinous, its Middle growing Fleshy near its Serrated Termination at the Curvature of the Ninth (q), Tenth (r), Eleventh (s), and Extremity of the Twelfth Ribs (t): The Ductus of Fibres of This passing Transverse, and those of the Precedent Descending Oblique; do Decussate each other in Acute Angles; which Riolan has well Ob­served,Anthrop. Lib. v. and contrary to the Opinion of Authors, assigns It with its Partner a different Use, in Depressing the Tho­rax, Both performing the Office of a Bandige in Binding together and Con­stringing the Posterior Muscles of the Spine, not unlike those constructive [Page 115] Inclosures of the Thigh and Cubit hereafter mentioned.

The Common Muscles referred to the Thorax, and appearing on the Backside, are the Sacrolumbi. How­ever We think these may be included among those of the Back, yet in imi­tation of most Authors we shall Treat of them in this place.

Sacrolumbalis.

This with the Dorsi Longissimus have their Origination in Common; Ex­ternally They are Tendinous as They spring from the Posterior part of the Spine of the Os Ilium (30), and Su­periorFig. xviii. Spine of the Sacrum (34), and all the Spines of the Vertebrae of the Loins (RR); Internally it Arises Fleshy, not only from those Parts, but from the Transverse Processes of the last named Vertebrae (u w x y z); whence with direct Fibres Ascending before it marches over the Last Rib (t) its di­vided into Two Fleshy Bodies, the Outward most of which is called Sa­crolumbus, whose Fibres ascend di­rectly, and make so many Thin Ten­dons as there are Ribs to whom they [Page 116] are Inserted; which are joined with so Accessory Muscles, Arising from each Rib, and united with them before their Insertions as they pass over the Superior, as Steno has well Observed.Specimen Myologiae. And This Order or Multiformed dis­position of it, is continued the whole length of the Thorax to the Third, Fourth, Fifth, and Sixth Vertebra of the Neck, which Superior Part is by Diemerbroeck made a distinct Muscle,Lib. v. Cap. vi. and called Cervicalis descendens. Now all the Muscles of the Head may be examined.

Splenius.

So called from its Figure, some­what representing an Oxes Spleen, It Ariseth partly Tendinous and partly Fleshy, from the four superior Spines of the Vertebrae of the Thorax (PP),Fig. xviii. which Lower part seems to be Distinct from its superior, which Ariseth from the Spines of the two Inferior Vertebrae of the Neck (f g): The former As­cending obliquely grows Fleshy, and becomes Tendinous again at its Inser­tion to the Second, Third, and Fourth Transverse Processes of the Vertebrae [Page 118] of the Neck (n n): The latter in likeFig. xviii. manner Ascending obliquely outward, grows Fleshy, and is so Inserted to the Occiput (2), part of it lying under the implantation of the Mastoideus (C).Fig. viii. Although this Muscle by Anatomists be reckoned amongst the Proper Muscles of the Head, yet when it Acteth it must necessarily move the Second and Third Vertebrae of the Neck (to which it is Inserted) ob­liquely backwards; But Acting with its Partner it pulleth them directly backwards.

Complexus.

Or Implicatus according to Lauren­tius, 'tis also called Tergeminus from its being said to have Three Begin­nings as some imagin, which we could never as yet observe in Dissection.Lib. v. Cap. xxi. It Ariseth with six Thin, small Ten­dons from the Transverse Processes of the Vertebrae of the Neck (nn), and inFig. xviii. its descent from thence becoming Thicker and more Fleshy grows partly Tendinous about its middle, where it is interwoven with various Orders of Fibres, and becoming still more Fleshy [Page 119] again, is so Inserted to the Superior part of the Os Occipitis laterally (2),Fig. xviii. and the back part of the Processus Ma­millaris (b); The Fibres of this MuscleFig. viii. D D D. are rightly observed to decussate those of the Former. Falloppius makesObservat. Anatom. that part of it which is Inserted to the Processus Mamillaris a distinct Muscle; It Arising from the Transverse Pro­cesses of the First, Second, Third, Fourth, and Fifth Vertebrae of the Tho­rax, and from as many of those of the Neck; which we have sometimes observed, but this not appearing so commonly, inclines us rather to think it a Lusus Naturae than a separate Muscle. Either of these Complexi Acting moves the Head backwards to one side; If both Act together, they assist the two Former. This with its Partner being raised, the Four follow­ing Muscles appear underneath, on each side.

Rectus Major.

This Ariseth partly Tendinous, but chiefly Fleshy from the Superior part of the double Spines of the Se­cond Vertebrae of the Neck, and in its [Page 120] Ascent becomes Broader and Fleshy, and is so Inserted to the Posterior part of the Os Occipitis. (EE.)Fig. viii.

This Muscle with its Partner Act­ing, pulls the Head directly back on the First Vertebra, (These being both raised, the Following will appear). This with the four subsequent Muscles are named from their Progress, Posi­tion, or Magnitude.

Recti Minores.

These are Two small Muscles ap­pearing both in sight at once, They arise Fleshy from the Posterior part of the first Vertebra of the Neck; and are so Inserted to the middle part of the Os Occipitis in two shallow Depres­sures of the said Bone. (HH.)Fig. viii.

These from their Use may be called Renuentes or Nodders Backwards, and are Antagonists to those we shall here­after describe and call Annuentes.

Obliquus Superior.

This Arising Fleshy from the Back­part of the Transverse Process of the First Vertebra of the Neck, and in its [Page 121] somewhat oblique Ascent becometh a Fleshy Belly, and lessening it self a­gain, is Inserted to the Os Occipitis la­terally. (FF.)Fig. viii.

By this, together with its Partner (they never Acting separately) the Head is moved Backwards on the first Vertebra.

Though the two Former Muscles seem adapted for all necessary mo­tions of the Head Backwards, yet it seems a provident Contrivance of Nature to add these; since the Recti Majores are by accident Extended when either of the Following Mus­cles Act in turning the Head to one side, whereby they are deprived of performing their Office at that time, but the first Vertebra of the Neck mo­ving with the Head; these Muscles are then imploy'd in Pulling the Head Backwards, as in looking upward to one side.

Obliquus Inferior.

This Ariseth Fleshy from the Ex­ternal part of the Spinal Process of the Second Vertebra of the Neck, close by the Origination of the Re­ctus [Page 122] major, and being dilated into a Fleshy Belly, passes obliquely to its Insertion at the Transverse Process of the First, where the Former Muscle begins. (G) When this acts on eitherFig. viii. side the Transverse Process of the first Vertebra of the Neck is moved towards the Spine of the Second; wherefore some Authors have reck­oned it amongst the Muscles of the Neck. But since the Head is also moved thereby, and the Face turned to that side on which it Acteth, it is not improperly reckoned amongst the Muscles that move the Head; it is Assisted by the Mastoideus. But of this more in its Order.

The Body must now be turned on the Back again, to examine the rest of the Muscles of the Head that appear on the Forepart, together with those of the Neck, of which the First is the Mastoideus which is best raised, by freeing it at its Origination on one side, and its Insertion on the other as in Chapt. XII. in Order to Dissect the Muscles of the Tongue, Os Hyoides and Larynx.

Mastoideus.

So called, because it is Inserted to the Mammillary Processe of the Tem­ple-Bone: It Ariseth partly Tendi­nous, and partly Fleshy from the UpperFig. xvii. part of the Os Pectoris (31) and near half the Clavicle; (14) with two (as it were distinct Originations, the first Ascending somewhat obliquely out­wards joyns with the Second, and marches up more directly, composing it Round, Thick, Fleshy Body, and as it passeth over the Upper part of the Musculus Levator Scapulae, becomes Broader again, at its Insertion to the Back part of the Processus Mamillaris (b)Fig. viii. and the Adjoyning part of the Os Oc­cipitis, (B) where the Splenius (above treated of) is Implanted. (P.)Fig. iv.

Anatomists not taking Notice of the true Insertion of this Muscle, have generally erred in their conje­ctures concerning its Use, supposing, that if both Act, the Head is bended Forewards, which Action, if rightly considered, cannot be performed by these Muscles, except the Vertebrae of the Neck are also inclined Forward [Page 124] with it, since their Insertion are right e Diametro opposite, if not behind the Articulation of the Head with the first Vertebra; which part of the Cranium (namely the Processus Mamillaris) nei­ther Ascends nor Descends in that A­ction: Wherefore it necessarily fol­lows, that when the Head is moved, either directly Forwards or Backwards on the first Vertebrae, these Muscles cannot Act. But if either of them Act, the Face is then turned to the contrary side; so when we look over the Left Shoulder, the Right Muscle Acts & vice versa; which may be observed in the naked Necks of li­ving Persons, and is commonly ex­prest by Painters. But if either of these Muscles should more and more contract, the Head is pulled down to one side forwards, as we see in Wry-Necks commonly so called; where one of these Muscles is always con­tracted.

The next Muscle that presents it self to the Knife, is partly described by Lib. de Musculis. Cap. x. Galen, and mentioned by Lib. ii. G. xxviii. Ves­salius belonging to the Back: Obser­vat. Ana­tom. Fallopi­us makes it his ninth pair of the Head. It is also mentioned by Riolan, [Page 125] Casp. Bauhin, Bartholomeus, Eustachi­us and others. Tho they are large Fleshy Muscles, and appear immedi­ately under the Gula or Pharynx, yet Spigelius and some others take no no­tice of them. They are likewise ex­prest by Bidloo, and called Recti in­terni: But we having observed an other small pair of Muscles under­neath them of a right position like­wise, deserving the Name of Recti, to distinguish which from those of the Back part, and these following Mus­cles we shall call them Recti interni Minores, and These, Recti interni Ma­jores.

Rectus internus Major.

This Arises Tendinous but chiefly Fleshy, from the Forepart of all the Transverse Processes of the Vertebrae of the Neck, except the first and second and in it's Ascent becoming Fleshy, passes over those two Superiour Ver­tebrae and is inserted to the Anteriour Appendix of the Os Occipitis near the great Foramen, that Transmits the Medulla Oblongata.

[Page 126]This manifestly Bends the Head Forewards, and therefore may be cal­led Flexor Capitis from its Use.

This with its Partner being remo­ved, the following Muscles appear underneath them.

Rectus internus Minor.

This and its Partner appear on the Forepart of the first Vertebrae like the Recti minores on the Back part, and arise near its Transverse processes and Ascending directly, are inserted to the Anteriour Appendix of the Os Occipitis immediately under the For­mer i. Fig. iii.

These nod the Head forward, and are Antagonists to the Recti minores as is above noted, wherefore they may be called Annuentes.

The last pair of Muscles which we shall Treat of belonging to the Head, are mentioned by Galen, and Accu­rately described by Falloppius in theseObservat. Anatom. Words, Ultimo loco notandi sunt Mus­culi duo admodum parvi qui A Processis Transverso Primae Vertebrae orti, valde graciles ascendunt ad Caput & in illud inseruntur prope Mammillarem processum. [Page 127] These we shall call Recti Laterales, from their Progress and Position; they may be also called Renuentes La­terales from their Use.

Rectus Lateralis.

This is a Short, Thick, Fleshy Muscle; Arising from the Superiour part of the Extremity of the Trans­verse Process of the first Vertebra of the Neck, between the Former and Obliquus Superior, thence Ascends di­rectly to its Insertion to the Os Occi­pitis in the Interstice made by the Processus Mammillaris and Styloides, k. Fig. iii. This nods the Head to one side.

Longus Colli.

This Arises partly Tendinous, but chiefly fleshy from the Fore-part of the Five Superiour Vertebrae of the Thorax, and being dilated in its mid­dle to a fleshy Belly, is Inserted to the Fore-part of all the Vertebrae of the Neck.

This with its Partner Acting bends the Neck right forwards. Between this and the Scalenus, (describ'd Chap. Cap. xi. XIX.) lies the Rectus internus Major, describ'd in the precedent Chapter, which Veslingius calls Musculus Bre­vius.

The Body must be now turn'd on its Face again in order to examin the rest of the Muscles that appear on the Back part of its Trunk.

Spinalis Colli.

So called, because it accompanies the Spines of the Neck, it arises from the Five Superiour Transvers Proces­ses [Page 129] of the Vertebrae of the Thorax, and Inferiour of the Neck, and in its As­cent becomes more Fleshy, and is so inserted largely into the Inferiour part of the Second Vertebrae of the Neck, laterally II. &c.Fig. viii.

These Draw the Vertebrae of the Neck directly backwards: Either of these Muscles being Raised, the Fol­lowing will appear underneath.

Transversalis Colli.

This Ariseth Fleshy from all the Transverse Processes of the Vertebrae of the Neck except the First and Se­cond, and is inserted after an ob­lique Ascending progress to their Su­periour Spines (K): It being a Conti­nuation of the same Series of Muscular Fibres that compose the Sacer and Semi-Spinatus, of which hereafter.

If either of these Muscles act, the Vertebrae of the Neck are moved obliquely Backward, as when we look over one Shoulder.

Besides these Muscles (which are al­ready Treated of by Anatomists) we observed in Dissection some Fleshy Bodies lying between the Bifurcated [Page 130] Spines of each Vertebra, which upon Examination proved to be so many Pair of Muscles, as there was Inster­stices between the said Spines. And in those Bodies that have the Spinal Process of the last Vertebrae somewhat Broader than it is commonly found; we have seen Five Pair of these Mus­cles, which from their Situation we call Interspinales Colli.

Interspinales Colli.

These are small Fleshy Muscles, arising from the Superior parts of each double Spinal Process of theFig. xviii. Neck (b, c, d, e, f,) except that of the Second Vertebrae (a), and are Inserted to the Inferior parts of all the said double Spines. LL. Fig. viii.

When these Muscles Act, they draw the Spines of the Vertebrae of the Neck nearer each other. These we first discover'd in the year 1690.

Dorsi Longissimus.

This Ariseth in Common with the Sacrolumbalis from the Spine of Os I­lium Fig. xviii. (30) and the Superior part of the Sacrum (34) and all the Spines of the Vertebrae of the Loins (RR); Externally Tendinous, Internally Fleshy, in its Ascent it is Inserted to the Transverse Processes of the Ver­tebrae of the Loins (S S S S) and as it marches over the last Rib (t), this great Muscle divides it self into Two, the Outermost of which is the Sacro­lumbalis as described Chap, the XXI; But the Innermost next to the Spine, is the Longissimus Dorsi, which Ascends with a partly Fleshy and partly Ten­dinous outside, and Fibres passing somewhat obliquely outward. Part of which Tendinous Fibres arise di­stinct from the Inferiour Spines of the [Page 133] Vertebrae of the Thorax (PP) and Su­periorFi. xviii. of the Loins (R R) from which likewise Arise some Fleshy Fi­bres Ascending obliquely Inwards, and are Inserted to the Fifth, Sixth and Seventh Spine of the Thorax (PP) as exprest by Bidloo, and called Semispi­nalis. Tab. 28. P. The other larger part of this Muscle ascending on the Thorax Tab. 29. KK. divides it self into many distinct Fleshy Portions not much unlike a Palm Branch, which are Inserted in a twofold manner to the Transverse Process of each Vertebra of the Tho­rax (O O O) and Tubercle of each Rib; as also to the Transverse Processes of the Vertebrae of the Neck (n n.)

When this, and its Partner Acts, they are not only Serviceable in keep­ing the Trunk of the Body erect and bending it backwards, but they are also useful in Progression, as it may be observed when either Leg is moved forewards; This Muscle on the same side is in Action, which to us seemeth to be advantagious in rendring the Os Ilium at that time stable, so that the Thigh may be the more com­modiously Elevated; in regard it is so [Page 134] moved by a Muscle arising from the Vertebra, above the Os Ilium, namely the Psoas.

(To examen this Muscle it is better to use the Fingers, or the pointed Handle of a Dissecting Knife, to divide it from its Companion, the Sacrolumbalis, and dis­cover its Ansulae, as Spigelius calls those parts of it which are Inserted to the Transverse Processes of the Vertebrae of the Back and Loins;) This being re­moved, the Proper Muscles offer themselves to view; first of those of the Loins.

Quadratus Lumborum.

This is a Short, Thick, Fleshy Muscle, situated in the Region of the Loins, or between the last Rib and Spine of the Os Ilium, it ariseth Fleshy from the Posteriour part of the Spine of the Os Ilium (30), and is in­sertedFi. xviii. to all the Tranverse Processes of the Vertebrae of the Loins inter­nally (u w x), under the Psoas Muscle▪ This like the Musculus Rectus Abdomi­nis, either moves the Vertebrae of the Loins nearer the Os Ilium laterally, when we are standing, on both Legs [Page 135] firm, or else moves the Os Ilium nearer the said Vertebrae, on the contrary side; when we stand upon one Leg only.

Sacer.

This may be also called Transversa­lis Lumborum. It lies under the Tendi­nous part of the Longissimus above men­tioned; It ariseth Fleshy not only fromFi. xviii. the Os Sacrum (34), but also from the Transverse Processes of all the Vertebrae of the Loins, and is inserted to their Superiour Spines. We have some­times observed a Spinalis Lumbo­rum like the Spinalis Colli above des­cribed, which Arising from the Supe­riour Spines of the Os Sacrum, and marching with direct Fleshy Fibres, isso Inserted to Superiour Spines of the Vertebrae of the Loins; The Transversalis Lumborum, now described lying under it.

Semispinatus.

This seems to be a meer continua­tion of the precedent Muscle, there­fore might not improperly deserve [Page 136] the Name of Transversalis Dorsi; it Ariseth Fleshy from all the Transverse Processes of the Vertebrae of the Thorax (OO), and marching obliquelyFi. xviii. upwards is Inserted to the Superiour Spines of the said Vertebrae (PP). These with the former, and Transver­sales Colli, Acting, move the whole Spine, or Vertebrae of the Neck, Back, and Loins, obliquely backwards, as when we endeavour to look very much behind us: If they all Act together on each side, they assist in Erecting the Trunk of the Body.

We need not wonder at the many Multiform Muscles inservient to the Ex­tention or Erection of the Head, Neck, Back and Loins, if we consider how much greater force is required to that end, in regard to the projecting fore­wards of the Head and Thorax; for as it appears in the Skeleton, Fig. xviii. we should on the other hand think it constantly liable to fall on its Face, were it not supported by these many strong Muscles; in which we have a plain Demonstration of the Immense Wisdom of the most Wise Architect, in Frameing a Structure projecting from its Fulcimen, which for several [Page 137] Ends (too numerous to specifie here) is to be moved Forewards, Backwards, and Sideways, and therefore by no other means could be supported so as to render it upon occasion Flexible, but by Muscles, since they only are capable of a greater Contraction and Relaxation than any other Springy Bodies composed of Ligaments, &c.

Thus having briefly Treated of all those Muscles, as yet known that appear in the Trunk of the Body; we come next to those belonging to the Artus, and first of those that move the Arm; two of which, namely, the Pectoralis & Longissimus, we were obliged to Dissect, Pag. 104. 112. to discover their Subjacent Muscles, but we shall now describe them amongst the rest▪ as the order of Dissection requires; for the convenient Performance of which, we are wont to take of the whole Arm to­gether, with the Scapula and Clavicula, by dividing the latter from the Os Pe­ctoris, by which means the trouble in examining the following Muscles is lessened, those moving the Scapula being Cut from it.

Pectoralis.

So called from its Situation. This hath a broad Semicircular, Fleshy be­ginning, above, from near half the Inferiour part of the Clavicula (14);Fi. xvii. Below, from the Os Pectorale (31), and all the Cartilaginous Endings of the six superiour Ribs, and from the [Page 139] Bony part of the seventh, it hath a distinct Fasciculus of Fleshy Fibres, (which sometimes we have seen con­founded with the Obliquus Descendens Abdominis) from this large Origin it marcheth Transversly, and becoming narrower but thicker, lessens it self as it passeth over the upper part of the Biceps Cubiti, and is Inserted by a short but broad strong Tendon, to the Superior part of the Os Humeri, above the Termination of the follow­ing Muscle.

The Fibres of this Muscle Decus­sate each other, near their Implantation to the Os Humeri; those of the Su­periour part running downwards, and those of the Inferiour marching up, Intersect the Former in Acute Angles.

When it Acts it moves the Arm either obliquely Upwards, or directly Forewards, or obliquely Downwards, according to the various Direction of its Series of Fibres.

Deltoides.

So called from its Figure, being like the Greek Δ. It hath a broad Origination, forewards from above one [Page 140] third of the Inferiour and ExternalFi. xviii. part of the Clavicula (11), where it is entirely Fleshy; Backwards it spring­eth partly Fleshy, but chiefly Tendi­nous from the whole Inferior Margin of the Spina Scapulae (16), from these places descending soon becomes Thick and Fleshy, growing narrower till it is inserted by its partly Fleshy, and partly Tendinous Apex, to the middle of the Os Humeri (17). This draws the Arm either directly upwards, or somewhat Forewards or Backwards according to the Direction of its diffe­ring Series of Fibres.

Supraspinatus.

So called because it is placed above the Spine of the Shoulder-Blade; It Ariseth Fleshy from the Superiour part of the Basis Scapulae (13), that is above its Spine, as also from the said Spine and Costa Superior of the Scapu­la (15), from thence passing between the Processus Coracoides (16), and Anchore­formis Fig. xvii. (15), it grows less and be­coming Tendinous, marches over the Articulation of the Humerus, joyning its Tendons with the following, is [Page 141] Inserted to the Head of the Os Hu­meri Fig. xvii. (20). The Proper Use of this Muscle is to lift the Arm upwards to­wards the Occiput.

Infraspinatus.

So called because it is placed be­low the Spine. This Arises Fleshy from the Inferiour part of the Basis Scapulae (13), as also from from itsFi. xviii. Spine (16), and Inferiour Costa (14), and Dorsum (12); from hence passing in a Triangular Form according to the Figure of the part, lessening itself as it marches over the Juncture it becomes Tendinous, and is inserted like the Former to the Head of the Os Humeri (19). This moves the Arm directly Backwards.

Teres Minor.

So called from its Figure and Mag­nitude, to distinguish it from the Fol­lowing.

This Muscle in some Bodies is con­founded with the Former, but in others we have found it distinct.

[Page 142]It Arises Fleshy from the Lower part of the Inferior Costa of the Sca­pula (14) and descends obliquelyFig. xviii. over the Superior Head of the Gemel­lus Major, where becoming Tendi­nous it is Inserted to the Head of the Os Humeri (19).

When this Acteth the Arm is mo­ved somewhat Backwards and Down­wards.

Teres Major.

This Arises from the Inferior Angle of the Scapula (13), and becoming a Round, Fleshy Body Ascends oblique­ly with the Former, but then passeth under the Superior Head of the Ge­mellus and makes a short, Flat Ten­don Inserted below the Neck of the Os Humeri close to that of the Fol­lowing.

Latissimus Dorsi sive Aniscaptor.

The first Appellation it receives from its large demensions, it with its Partner covering the whole Back.

The latter from the use that is sometimes made of it. Its Thin, [Page 143] Broad, Tendinous Origination is continued from the Seven Inferiour Spines of the Vertebrae of the Thorax (PP), and all those of theFig. XV Loins (RR) and Superior of the Os Sacrum (34), and the Posterior part of the Spine of the Os Ilium; (30) beginning to grow Carnous as it pas­ses over the Longissimus Dorsi and Sa­crolumbus, and in its Progress over the Curvated part of the Ribs it receives several Fasciculi of Fleshy Fibres Ari­sing from thence, which by their Con­junction compose a Thick Body, still lessening it self in its demensions as it marcheth towards the Axilla and running over the Inferiour Angle of the Scapula, from whence sometimes does Arise a Fleshy part of it, which I have Observed in those Bodies in whom the Teres Minor was absent, is at last inserted by a Short, but Flat Strong Tendon to the Os Humeri near the Former.

The next Muscle that presents it self, is the Coracobrachialis, by some called Perforatus, which is described by Galen and Vesalius with the Internal Head of the Biceps Cubiti.

Coracobrachialis.

So called from its Origination and Insertion; it Arises partly Fleshy and partly Tendinous from the Extremity of the Processus Caracoides Scapulae, (16)Fig. xvii. and in its descent it becomes larger, strictly adhering to the Internal Ten­dinous Beginning of the Biceps, and parts from it near its Tendinous In­sertion at the middle of the Internal part of the Os Humeri (18). Through this Muscle passeth a Large Nerve; wherefore by some it is called Perfo­ratus.

When it Acteth the Arm is moved Upwards, and turned somewhat Ob­liquely Outward.

Subscapularis.

So Named from its Situation, by some called Immersus. It is a Large Fleshy Muscle, filling he Internal Con cave part of the Scapula (17); Arising Fleshy from its whole Basis and Supe­rior and Inferior Costa Internally, and marcheth forward, lessening it self ac­cording [Page 145] to the Demensions of the Bone, and passing over the jun­cture, is Inserted in a Semicircular Manner to the Neck of the Os Hu­meri (20).Fig. xvii.

When this Acteth, the Os Humeri is Pulled nearer the Trunk of the Body. The Tendon of this Muscle together with the Supra and Infraspi­natus and Teres Minor unite near their Insertions, and Environ the Articula­tion of the Os Humeri with the Sca­pula not unlike the Ligamentum latum of the Coxa, to prevent frequent Lux­ations: And by their Successive Al­ternate Acting, the Arm is moved Circularly.

Biceps.

Because it hath two Heads or Be­ginnings, the First or Outmost, Arises with a long Round Tendon from the Upper Part of the Brink of the Ace­tabulum Scapulae, (17.) and runs underFig. xvii. the Ligament of the Articulation in a Sulcus or Channel on the Head of the Shoulder-Bone, wherein it is in­closed by a proper Ligament. In its Descent it begins to grow Fleshy as it marcheth under the Termination of the Pectoral Muscle, where dilating it self into a Large Fleshy Body, it joyns with its other Head or Begin­ning. The Latter Ariseth with a somewhat Broad, Flat and Long Ten­don at the Extremity of the Processus Caracoides Scapulae (16); in its descent it strictly adheres to the Coracobrachia­lis (wherefore some Authors not rightly describing that Muscle a­mongst those of the Arm, have mi­staken it for a Fleshy Beginning of this) But then parting from it, both these Heads compose a Large Fleshy Belly, which becoming Tendinous [Page 147] near the Cubit, is commonly said to be Inserted by a Strong, Round Ten­don to the Tubercle at the Upper Head of the Radius, (25.) But weFi. xvii. have observed this Tendon to be dou­ble, the External of which being Thin passeth obliquely over the Musculus Pronator Radii Teres, and Membrane like expanding it self, joyns with the Membrana Communis Musculorum, which Embraceth all the External Muscles of the Carpus and Fingers.

When this Muscle Acteth the Cubit is Bended.

The double Tendinous Termina­tion of this Muscle, (tho' not taken Notice of by any Author that we know) is very evident, and was ob­served first by us, some years since in Dissecting these Muscles, in Compa­ny with our very good Friend, that most Indefatigable and Curious Bota­nist Mr. Samuel Doody. It appeareth immediately under the Skin and Mem­brana Adiposa of the Cubit.

As for the use of this External Tendon which we call Fascia Tendi­nosa, it seems designed not only for the more advantagious Elevation, or [Page 146] [...] [Page 147] [...] [Page 148] Bending of the Cubit, which it more easily moves, by how much the more it recedes from the Centre of its Motion or Fulcimen at the Lower part of the Arm-Bone, (23) and approach­ingFig. xvii. to its other Extream; But like­wise strictly including all the Exter­nal Muscles, whether belonging to the Radius, Carpus, or Fingers, it thereby Corroborates them in perfor­ming those strenuous Actions they are necessarily employ'd in. This Latter Use was first suggested to us by observing those Artificial Banda­ges made of Leather which some La­borious Mechanicks make Use of (by Adapting them to the Belly'd part of the Muscles of the Cubit) amongst which Turners and especially those that use the Rasp in making the Frames for Cane-Chairs (as they are commonly called) like a double Screw, are frequently obliged to this Artifice.

In Phlebotomy the ductus of these External Tendinous Fibres ought to be respected by directing the Laun­cet according to their Length, to avoid too great a division of them which is frequently the Occasion of [Page 149] those ill Symtoms that remain after that so commonly Practised Opera­tion by Bold Blood-Letters.

An extraordinary Case relating to this Muscle once happened in our Practice. A Woman, three days be­fore she consulted us, had, (as she suspected) Dislocated her Shoulder-Bone by wringing of Linnen Cloaths after washing (which is commonly done to express the Water) adding, that in straining her Arm, in that Action, she sensibly felt something (as she thought) slip out of its place on her Shoulder. After examining the part, we were well satisfied that there was no Dislocation: But ob­serving a Depressure on the External part of the Deltoide Muscle, and finding the two Inferior Tendons of this Biciptal Rigid, and the Cubit thereby denied its due Extention, we suspected that the External Tendinous Beginning, (before taken notice of) was slipt out of its Channel in the Os Humeri; but finding the part at that time somewhat Inflamed, she ha­ving not long before made use of it. We advised her to an Emollient Ap­plication, and to give it rest till the [Page 150] next morning, at which time we found our Conjecture true, and by turning the whole Arm to and fro, it readily slipt into its place, she recovering the use of the Part immediately.

Brachioeus Internus.

This derives its Name from its Si­tuation, lying partly under the For­mer, It Ariseth Fleshy from the Inter­nal part of the Os Humeri (18) at theFig. xvii. Insertion of the Deltoides and Caraco­brachialis Muscles, and descending o­ver the Juncture of the Cubit with the Arm-Bone, it's Inserted partly Fleshy and partly Tendinous to the Superior and Fore-part of the Ulna (26). This is also a Bender of the Cubit.

Gemellus.

So called from its double Origin, It Ariseth first Tendinous from the Superior part of the Inferior Costa of the Scapula (14) internally, and as itFig. xviii. passeth between the two Round Muscles it grows Fleshy, and in its Descent joineth with its other Begin­ning, which Ariseth Broad and Fleshy [Page 151] from the Upper and Back part of the Os Humeri, under the Deltoid Muscle, and being Tendinous on the outside and Fleshy within, is so Inserted to the Superior and External part of the Ulna called Olecranum, and Ancon, or the Elbow. (24.)Fig. xviii.

Its use is to Extend the Cubit; If we examin the two beginnings of this Muscle we shall find them interwoven with various Orders of Fibres, where­by it is rendered capable of perform­ing the Extension of the Cubit with a greater strength, which appears in Tumblers when they are Walking on their Hands, who by an Immediate Extension of their Cubits can return to their Feet.

Brachiaeus Externus.

This seems to be the Third Begin­ning of the former Muscle, its Ori­gination is continued from above the middle of the Inferior and Back part of the Os Humeri (17), to its Cavity, which receives the Olecranum (24) in the Extension of the Cubit, where joining with the Tendinous outside of the Former, it is Inserted with it, as abovesaid.

Anconaeus.

So called by Riolan from its Situa­tion, It Ariseth Fleshy from the Infe­riorLib. v. Cap. xxv. and Back-part of the Os Humeri (20), growing larger as it marchethFig. xviii. between the Superior ends of the Ulna and Radius, and is Inserted Fleshy to the Lateral part of the For­mer a Thumbs length below the Ole­cranum. (24.)

This is also an Extender of the Cubit.

The Muscles of the Palm of the Hand offer themselves to be Dissected, before we can Examin Those of the Carpus, Fingers, and Radius.

Palmaris Longus.

This has an Acute Beginning from the Internal Extuberance of the Os Humeri (22), and soon becoming aFig. xvii. Fleshy Belly, and contracting it self again to a Long, Flat, Slender Ten­don, marches obliquely with the Ten­don of the Flexor Carpi Superior, and passing over the Ligamentum Anulare where it expands it self, and cleaves firmly to the Skin of the Palm, is In­serted to the roots of the Fingers la­terally; It being there divided to Transmit the Tendons that Bend them.

Columbus observes the long Begin­ning of this Muscle from the Extube­ranceLib. v. C. xxxiii. of the Os Humeri is sometimes wanting, which observation is also confirmed by our Experience. It As­sists in firmly, grasping any Tactile Body, and defends the subjacent Ten­dons from External Injuries.

Palmaris Brevis.

By Spigelius called Caro Musculofa Lib. v. C. xxxv. Quadrata. Anatomists have been ex­treamly deceived in their Idea's of this Muscle; it not Arising from the Mem­brana Carnosa, as Columbus pretends, or from the Eighth Bone of the Carpus, as Falloppius Writes; but it springethObservat. Anatom. with a Broad Membrane-like Tendon from the External part of the Os Meta­carpi Minimi Digiti, and one of the Bones of the Carpus; whence Ascend­ing over the Abductor Minimi Digiti it becomes a Thin Disgregated Fleshy Muscle, marching under the Tendi­nous expansion of the Former in the Palm, and is Inserted by a short, strong Tendon, to the Eighth Bone of the Carpus.

This Acting Draws the Mons Lunae towards the Os Metacarpi Minimi Di­giti, whereby the Palm becomes hol­low; contrary to the Opinion of Spi­gelius, who pretends it Extends the Hand when we open it; which is not done by any proper Muscle, but by the Common Extenders of the Fingers.

Perforatus.

So called because its Tendons are Perforated to admit Those of the following Muscles to pass thorough [Page 156] Them to their Insertions; It is also call'd Sublimis from its Situation, be­ing above the Following; and Flexor secundi Internodii Digitorum from its Use. It Ariseth Tendinous from the Internal Extuberance of the Os Hu­meri (22) between the Flexores Carpi; Fig. xvii. it also has a Disgregated Fleshy Ori­gination from the Fore-part of the Radius, between the Pronator Radii Teres and Flexor Pollicis Magnus, com­posing a Fleshy Belly lessens it self in less then half its progress, where it's divided into Four Fleshy Portions, each of which soon becomes so many Roundish Tendons, and are included in their proper Mucilaginous Mem­brane as they pass under the Liga­mentum Transversale Carpi through the Palm; near the first Internode of the Fingers each Tendon is divided to admit those of the following Muscle to pass through them, then joining, and subdividing again, immediately before they are Inserted to the su­perior part of the second Bone of each Finger (30.)

This and the following Muscle are Accurately exprest by Bidloo, Tab. 67.

Perforans.

Because its Tendons run through those of the Former, it's also called Profundus from its Situation, and Tertii Internodii Digitorum Flexor from its Use. It Ariseth Fleshy from near two Thirds of the Superior and Fore-part of the Ulna (26), as also from theFig. xvii. Ligament between the last named Bone and Radius, becoming a Large Thick Bellied Muscle, grows out­wardly Tendinous before it passes over the Pronator Radii Quadratus, and is divided into Four Round Tendons which march under those of the for­mer Muscle beneath the Ligamentum Transversale abovementioned, (from each of these Tendons the Musculi Lumbricales are said to Arise) after which they pass through the Fissur's of those of the Former, and proceeding over their extremities, Terminate in the superior and fore-part of the third Bone of each Finger. (30.)Fig. xvii.

The Tendons of the last described Muscle running through those of the Precedent, is a no less Useful then Stu­pendous Artifice in Nature.

[Page 158]To the end the Fingers (like so many Leavers) should be Bended with great Force, it is absolutely necessary the strongest Muscle should be Insert­ed nearest their Extremities, and far­thest from their Fulcimina the Ossa Me­tacarpi: But in regard every Inter­node should be attended with a parti­cular Muscle, the better to accommo­date them to various Imployments, and the Origination of the superior or Perforatus is confined to the Apex of the Internal Extuberance of the Os Humeri and upper part of the Radius only, wherefore could not be a fit In­strument for so Strenuous an Action, and that not only in regard to its Magnitude, but by the Approach of its two Extreams when the Cubit or Carpus are Bended; both which would be no small impediments in divers Actions; it's therefore necessary it should be imployed in the Motions of the second Internodes: But since these superior Tendons would be hereby liable to interrupt the Inferior in their Right progress to the Extremities of the Fingers, it seems an Argument of great Counsel in transmitting the Lat­ter through the Fissures of each of the [Page 159] Former, whereby the Actions of Both are not only distinctly performed, and the extremities of the Fingers attend­ed with the Largest Muscle, (whose Origin is below the Os Humeri, where­fore its Extreams cannot approach in the Flexion of the Cubit) but their Motions are preserved, though the Superior Muscle is totally divided, which indeed is a Provident Contri­vance of the Author of Nature, and is in it self sufficient to excite our Ad­miration.

Lumbricales.

So called from their Figure, being not much unlike the Common Earth­worms; they are also called Flexores Primi Internodii Digitorum from their Use. Anatomists generally derive the Originations of these Muscles from the Tendons of the last treated of; but in a Subject which we lately Dis­sected I observed part of that Lum­brical Muscle belonging to the Fore-Finger had a distinct Fleshy Original, and a long slender Tendon lying be­tween the Two Preceeding; which suggested to me that the other Three [Page 160] and those of other Subjects have their Beginnings in common with the Per­forans, and Uniting with its Tendons are afterwards Disunited again, and growing Fleshy pass to their Tendi­nous Implantations with the Interossei at the first Internode of each Finger externally laterally next the Thumb.

These we suppose perform those Minute Motions of the Fingers when the Second and Third Internodes are Curvated by the two last treated of Muscles; and therefore Used in play­ing on Musical Instruments, and may be thence Named Musculi Fidicinales.

Extensor Digitorum Communis, seu Digi­torumBid. T. 69. G. Tensor.

This has an Acute Tendinous Ori­gination from the outward Extube­rance of the Os Humeri (20) betweenFig. xviii▪ the Extensores Carpi becoming Fleshy, in less than half its progress its di­vided into three Portions which be­come so many Tendons (of which the Middlemost is the Longest) passing under their Annular Ligaments be­tween the Lower parts of the Ulna (23) and Radius (22) march sepa­rately [Page 161] over the Dorsum Manus, and remitting. Tendinous Filliaments to each other as they pass the First In­ternodes of each Finger, and are af­terwards Inserted to the superior parts of the First, Second, and Third Bones of the Fore, Middle, and Third Fin­gers. (28.)Fig. xviii.

There being no Force required in the Extension of the Fingers, we need not wonder that the Muscles im­ployed in that Office are no Larger in Proportion to their Antagonists.

The Proper Muscles of the Fingers now offer themselves to the Knife, which we shall Treat of in the Order they are above Named.

Interossei Manus.

These are Distinguished into Exter­nal and Internal, They are aptly named from their Situation: Authors disagree in their Number, some reck­oning Six, others Eight, amongst which they esteem the Abductor Minimi Digiti and Indicis, but we rather incline to the First Opinion, conceiving the Two latter named Muscles do not deserve these Denominations. They Arise Fleshy [Page 162] Internally in the Palm from the supe­rior parts of the Metacarpal Bones (28) next the Carpus (27), whenceFig. xvii. descending between the last named Bones they become Tendinous at the first Internode of each Finger lateral­ly, and pass to their Insertions with the last Treated of Muscle. Each Interstice of the Metacarpal Bones en­tertaining Two Muscles Inserted to the sides of the Fingers.

When all these Interossei Act toge­ther they Draw the Fingers nearer each other, and Assist in their Exten­sion, as Galen takes notice, at whichLib. i. De Us. par. C. 18. time they together with the Abductor Indicis and Minimi Digiti are capable of Divaricating the Fingers, which Action cannot without some Difficulty be performed by them when they are Bended; which Contrivance of the Most Wise Architect is also observed by Galen. Loco supra citato.

Extensor Indicis seu Indicator.

It Arises Fleshy from the middle of the External part of the Ulna (23)Fig. xviii. next the Radius (22), immediately below the Extensores Pollicis, and [Page 163] descending obliquely becomes Tendi­nous as it passes under its Annular Ligament at the Lower part of the Radius and Carpus (25), passing overFig. xviii. the Os Metacarpi Indicis, and joining with the Tendon of the Extensor Com­munis, is Inserted with it to the supe­rior part of the 3d Bone of the Fore-Finger. The Tendon of it is some­times divided. Its Name Declares its Use.

Abductor Indicis.

This is not to be seen till the Ab­ductor Pollitis is Raised; by some it is reckoned amongst the Interossei as a­bove noted. It Arises Fleshy from the Os Metacarpi that sustains the Fore-FingerFig. xvii. (28), and descending over the First Internode of the said Finger be­comes Tendinous, joining with the Tendon of one of the Lumbrical Muscles, and is Inserted with it toge­ther with the Tendon of the former Muscle. Its Name intimates its Use, in Drawing the Fore-Finger from the rest.

Extensor Minimi Digiti.

This Arises partly Tendinous at the Extremity of the External Apo­physis of the Os Humeri (20), andFig. xviii. partly Fleshy from the superior part of the Ulna (23), between the Ex­tensor Communis Digitorum and Muscu­lus Ulnaris Extensor, and becoming Tendinous as it passes under the Li­gamentum Annulare at the Carpus (25); it is there divided into Two, some­times three Tendons, which are U­nited into one at its Insertion to the superior part of the 3d Bone of the Little-finger: Its Name Declares its Action.

Abductor Minimi Digiti.

This Appears in some Bodies divided into Two or Three Muscles, having each a differing Series of Fibres; The First of which seems to be a Flexor primi Internodii Minimi Digiti; The Second an Abductor of the same; The Third Abductor Se­cundi and Tertii Internodii: But this Division is not Constant, wherefore [Page 165] we shall Describe it as One Muscle, lest we might appear inclinable to multiply their Number, which has been a Vice amongst some. It Arises Fleshy First from the Ligamentum Transversale, and Fourth Bone of the Carpus; Secondly from the Third Bone of the Carpus; Thirdly and lastly from the superior part of the subjacent Os Metacarpi: The two First continue Fleshy to their Insertions; the Former Terminating at the supe­rior part of the First Bone of the Little-finger forwards, the Latter end­ing at the same part of the said Bone laterally; the Third and Last be­coming Tendinous like the Interossei, is Inserted like them with the Tendon of the Extensor Minimi Digiti at the superior part of the 3d Bone of the Little-finger.

Flexor tertii Internodii seu LongissimusBid. T. 68. L. Pollicis.

This we have frequently observed to have a Twofold Beginning; the first and superior of which Ariseth Acutely from the Internal Extuberance of the Os Humeri (22) between theFig. xvii. Perforatus and Perforans, becoming a Fleshy Belly and then Tendinous joins with the Middle Tendon of its other Larger Head: The second or Inferior Origin of this Muscle (is that part of it which is commonly Described) A­rising [Page 167] with a Double Order of Fleshy Fibres for some space on the Radius (25), from immediately below itsFig. xvii. superior part, which uniting in a middle Line or Tendon (not unlike the Fibrillae of a Feather joining to their Stamina) which passing over the Ar­ticulation of the Carpus becomes en­tirely Tendinous as it runs over the Flexor primi & secundi Internodii to its Implantation at the superior part of the 3d Bone of the Thumb (29): For the better Dissection of the rest of the Muscles of this Part, Raise the Abductor Pollicis.

Abductor Pollicis.

This Arises Broad and Fleshy from the Internal part of the Ligamentum Transversale Carpi, whence Descending lessens it self, and becomes Tendi­nous at its Implantation to the supe­rior and external part of the second Bone of the Thumb laterally.

This Draws the Thumb from the Fingers, from whence it derives its Name.

Flexor primi & secundi Ossis Pollicis.

This is a Large Disgregated Fleshy Muscle Arising from the Ligamentum Transversale Carpi Bones of the Carpus (27)Fig. xvii. at the Basis of the Mons Lunae and Os Metacarpi (28) of the Middle Finger, whence passes to its Insertion partly to the Ossa Sesamoidea of the second Internode, and partly to the first Bone of the Thumb. This may be divided into Three, as Vesalius writes, and Bidloo has Figured it Tab. 68. M, NN, OO, P. Its Actions are various accord­ing to the diversity of its Series of Fibres; so it Bends the First or Second Bones of the Thumb either directly, or obliquely towards the Carpus, and Volam Manus.

Adductor Pollicis.

This Arises Tendinous in Common with the Abductor Indicis, becoming Fleshy Ascends obliquely to its Broad Termination at the superior part of the first Bone of the Thumb (29). This brings the Thumb nearer the Fore-finger.

[Page 169]The rest of the Muscles employed in the Motion of the Thumb are Ex­tenders: Though Anatomists gene­rally reckon but Two of them, yet it does not occur to our memory we ever found less than Three distinct Fleshy Muscles, neither do the Figures (that seem to be done after the Life) in Vesalius and Bidloo exhibit them o­therwise.

Extensor primi Internodii Pollicis.

This Arises Tendinous from the upper part of the Ulna (23) imme­diatelyFig. xviii. below the Supinator Radii bre­vis, soon growing Fleshy, and be­comes Tendinous again as it Descends obliquely over the Tendons of the Radialis Extensor, and is Inserted to the superior part of the First Bone of the Thumb (27). This we have sometimes found divided into Two and sometimes Three distinct Muscles.

Extensor secundi Internodii ossis Pollicis.

This Arises Broad and Fleshy from that part of the Radius (22) next the Ul­na [Page 170] (23), and becoming TendinousFig. xviii. passes under the same Involucrum with the Tendons of the Former to its Im­plantation of the superior part of the second Bone of the Thumb.

Extensor tertii Internodii Ossis Pollicis.

This has a Broad, partly Tendi­nous, but chiefly Fleshy Origination from the Ulna, immediately below the Beginning of the Extensor primi Inter­nodii, or between it and the Indicator, as also from Ligament between the last named Bone and the Radius, whence Descending obliquely, be­coming Tendinous as it marches in a proper Sinus on the inferior Appendix of the Radius, wherein its Inclosed by its Annular Ligament, and passes over the Two Tendons of the Radialis Extensor to its Insertion at the supe­rior part of the Third Bone of the Thumb.

When this Acts it does not only Extend the Thumb, but Brings it somewhat Backwards, in so much that some can place it on the superior and Back part of the Ossa Metacarpi.

Flexor Carpi Radialis.

This Ariseth Tendinous from the Internal Extuberance of the Os Hume­ri (22) Becoming Fleshy adheresFig. xvii. strictly to the Pronator Radii Teres, and in half its oblique Progress to the Car­pus (27), it becomes a Flat Tendon which passeth over the Annular Liga­ment, and is Inserted to the Upper Part of the Os Metacarpi (28) which sustains the Fore-finger.

Flexor Carpi Ulnaris.

This Ariseth Tendinous from the same Tubercle of the Shoulder-Bone with the Former, as also from the Su­perior and External Part of the Ulna [Page 172] (26) where the Musculus Perforans dothFig. xviii. Arise, and continuing Fleshy accord­ing to the length of the Ulna is partly Inserted by a Short, Strong Tendon into the Fourth Bone of the Carpus, and partly into the Os Metacarpi which sustains the Little Finger.

Their Names declare their Use.

Extensor Carpi Radialis.

By some called Bicornis and Radiaeus Externus. It hath Two Beginnings, and indeed seems to be Two distinct Muscles, the Outermost Arising Fleshy above the External Protuberance of the Os Humeri (20), immediately be­low the Supinator Radii Longus, in its descent becomes a Fleshy Belly, and grows Tendinous above the middle of the Radius (22): The other Begin­ning of this Muscle is partly Fleshy and partly Tendinous Below the For­mer, either from the Apex of the Ex­tuberance of the Os Humeri or Supe­rior Part of the Radius, and continues Fleshy somewhat Lower than the Su­perior; Both Tendons marching un­der the Extensores Pollicis, run under the Ligamentum Annulare, and are In­serted [Page 173] to the Superior Parts of the Ossa Metacarpi of the Fore, and Middle Fingers. (26.)Fig. xviii.

Extensor Carpi Ulnaris.

This hath an Acute Tendinous Be­ginning from the Outward Extube­rance of the Os Humeri (20), and becomes Fleshy as it Descendeth ac­cording to the length of the Cubit, growing Tendinous again as it march­eth over the Inferior part of the Ulna (23), and passing under the An­nular Ligament, It is Inserted to the Superior Part of the Metacarpal-Bone of the Little Finger. (26.)

If this Muscle and the Ulnaris Flexor Act, they move the Hand side­ways towards the Ulna, and in like manner if the Radialis Flexor and Ex­tensor Act, they move it towards the Radius. It is well observed by most Authors, that the Extenders, whether belonging to the Fingers or Carpus Arise from the Outward Extuberance of the Os Humeri, and their Antago­nists the Flexors, from the Internal Protuberance of the same Bone, as also from the superior and external [Page 174] part of the Ulna next the Anconeus (above treated of.)

Pronator Radii Teres.Vesal. M. T. i. v.

By some called Pronator Superior Ro­tundus; It Ariseth Fleshy from the In­ternal Extuberance of the Os Hume­ri (22), where those Bending theFig. xvii. [Page 175] Carpus and Fingers do Arise, and Firmly adhering to the Flexor Carpi Radialis, It Descends obliquely Down­wards to its Fleshy Insertion, a little above the Middle of the Radius (24)Fig. xvii. Externally.

Pronator Radii Quadratus.Bid. T. [...]8. B.

Or Inferior Quadratus, It Ariseth Broad, and Fleshy, from the Lower and Inner part of the Ulna (26), and passing Transversly over the Liga­ment, that joins the Radius to the Ulna, and is so Inserted to the Superior and External part of the Radius.

Supinator Radii Longus.Ibid. C.

This Ariseth Broad and Fleshy from the Superior and External part of the Os Humeri (17) three Fingers breadthFig. xviii. below the Termination of the Del­toides, and Descending obliquely in­wards, It gradually lessens it self, and becomes a Flat, Broad Tendon, which likewise grows narrower till it is Inserted to the External and Inferior part of the Radius (24) near the Car­pus. (27.)Fig. xvii.

Supinator Radii Brevis.Bid. T. 71. G.

This Ariseth partly Tendinous and Fleshy from the Superior and Exter­nal part of the Ulna (24) next theFig. xviii. Radius, and passing obliquely Trans­verse over that Bone, is so Inserted to its Superior part below the Promi­nence of the Radius, where the Round Tendon of the Biceps endeth. (25.)Fig. xvii.

We come next to the Muscles of the Thigh, Leg, and Foot, though Riolan sharply reprehends Gaspar Bauhin in his Animadversions on his Theatrum Ana­tomicum for Male-administration of the Muscles of the Leg before those of the Thigh, alledging that those of the Former may be all demonstrated, and the Latter remain untouched, yet we cannot agree with him in that particular, knowing it to be absolutely necessary to separate diverse Muscles of the Tibia, as well as to cut off some of those moving the Os Femo­ris it self, before we can have a tolerable prospect of others; especially the Ro­tator Femoris Extrorsum. However since some Muscles which belong to the Thigh do Arise from the Vertebrae of the [Page 177] Back, Loins, and Os Sacrum, we shall begin with them First; and then divide the Os Ilium from the Sacrum, and remove the Trunk of the Body, which Practice is not only convenient for Dissection, in respect the Limb is more easily turned to and fro upon the Table, but in publick Demonstrations is done to avoid an offen­sive Scent Apt to arise from the Trunk. This done, proceed to divest the rest of the Muscles of their Common Teguments the Skin, Fat, and Membranes: Taking care that the Fascia Membranosa of the Thigh and Leg be not wounded, and that you likewise take off all the Fat in the Planta Pedis, and avoid Cutting the Long Tendon of the Musculus Planta­ris as it descends internally by the great Tendon of the Gasterocnemii near the Os Calcis.

Psoas Parvus.

Though This ought to be counted amongst Those belonging to the Loins, yet its subserviency to the Great Psoas, & for our better convenience in Dissection, we chuse rather to reserve it for this Place. It Arises Fleshy from the superior part of the First Vertebrae of the Loins internally laterally within the Abdomen, imme­diately below the Cavity of the Dia­phragm, whence descending obliquely Inwards towards the Pelvis Abdominis [Page 180] (where it ceases to be Fleshy) in a manner embracing the Great Psoas, and is Inserted with a Thin, Broad, Strong Tendon, to that part of the Os Pubis (40), where it is joined toFig. xvii. the Os Ilium. This Muscle with its Partner Acting assist the Recti Abdo­minis in drawing the Ossa Pubis up­wards, as in raising our selves from a Decumbent Posture. Thus Rope­dancers hang by their Hands, and Raise the Inferior parts of their Bo­dies to take hold of the Rope with their Feet. Though their proper Action is to bend the Loins, yet their Tendons embracing the Two follow­ing Muscles (which we have frequent­ly observed to extend over their infe­rior parts) not unlike the Fascia Ten­dinosa Cubiti and Lata of the Thigh, do also Corroborate them in their Action.

Psoas Magnus seu Lumbales.Vesal. M. T. 8. ☉. Bid. T. 52. K. K.

So call'd from its Situation, Its a Round, somewhat Large and Fleshy Muscle, Arising from all the Vertebrae of the Loins (34), and their Trans­verseFig. xvii. Processes (w x y z) internally [Page 181] and laterally, within the Cavity of the Abdomen; from thence descend­ing over the superior part of the Os Sacrum (35), and Spine of the Ilium Fig. xvii. (37), where it's joined with the Fleshy Fibres of the following Muscle; with which its inseparably united at their partly Fleshy and partly Tendinous Insertions in the Inferior part of the lesser Trochanter of the Thigh-Bone. (46)

This assists the Following in its Action.

Iliacus Internus.Bid. T. 52. N N.

This Arises Fleshy from above half the Superior Region, and Internal concave part of the Os Ilium (36), and in its descent over the Inferior part of the last named Bone (40), joins with the Former, and is Inserted with it as above-said, partly under the Termination of the Following. This together with the Former move the Thigh Forwards in Progression.

Pectineus.Spigel. L. 4. T. 31. not let­ter'd.

So called from its beginning at the Os Pubis or Pectinis (38). It has a [Page 182] Thick, Broad, and Fleshy Origina­tion from the External part of the said Bone, between the Two last de­scribed Muscles and second Head of the Triceps, and Descending Oblique­ly Backwards it becomes a flat strong Tendon near its Implantation to the Asperity (37) on the Posterior part ofFig. xviii. the Os Femoris, immediately below the Lesser Trochanter, at the Insertion of the Two Former Muscles.

This Acting together with the Two Preceeding, do not only Draw the Os Femoris Upwards, but directs it Outwards, by its Curve descent from its Origination to its Insertion at the posterior part of the Os Femoris; which is a Provident contrivance of Nature in Walking since the Thigh­bones by their Oblique position do thereby render the Toes liable to turn Inwards. These Three last treated of Muscles, besides the Recti Abdomi­nis and Psoi parvi, seem to serve for the Inflexion of the Body, and Direct the whole Limb, to wit, the Thigh, Leg, and Foot outward in a more Graceful Step.

[Page 183] The Musculus Membranosus presents it self next to the Knife; therefore must be Raised before we can gain a View of the rest which move the Thigh bone. This may be done, either by cutting it from its Fleshy Origination at the point of the Spine of the Os Ilium (37), and Fig. xvii. turning it Downwards; or after its well cleared of the Skin, Fat, and Mem­branes, it may be Raised contrarywise by cutting off its Tendinous Insertion at the superior Appendix of the Fibula (53), and Freeing it from all the Muscles of the Tibia, and leaving it at its Origination: Either of these being done, proceed to Raise the Pyriformis from its Origin within the Pelvis of the Abdomen (40), and part of the Fleshy Beginning of the Glutaeus Major from the External part of the Os Sacrum (34) and Coccygis (0).Fig. xviii. The Bodythen being laid in a Supine Po­sture, and the Legs Divaricated; with a Thin Knife divide the Os Ilium (36)Fig. xvii. from the Sacrum (35.)

Glutaeus Major.Vesal. T. 9. [...]. T. 10. K. Spigel. T. 29. L. 4. CC.

So called from its being the largest Muscle of those which compose the Buttocks It has a large Semicircular Beginning; Forwards meerly Tendi­nous, from near two Thirds of the External Part of the Spine of the Os Ilium (30); Backwards its Origina­tionFig. xviii. is Thick and Fleshy from the Po­sterior part of its Spine, and hindmost part of the Sacrum (34) laterally, and whole Os Coccygis (O) as also from a Broad Ligament that's extended be­tween the two last Named Bones and Tubercle of the Os Ischium (31); its Fleshy Fibres Descending Disgregate­ly in an almost semicircular manner become Tendinous as they approach the Great Trochanter (40), where its United with its First described Ten­dinous Beginning, Descending over the External part of the Great Tro­canter, after being joined with the Tendon of the Membranosus, proceeds to cover and strictly Embrace all the External Muscles of the Tibia like the External Tendon of the Biceps Those of the Cubit: But the other part of [Page 185] it proceeding from the Fleshy Body of this Muscle, is largely Inserted to the Linea Aspera (37) on the BackFig. xviii. part of the Os Femoris, near Four Fin­gers breadth below the Great Tro­chanter.

The first described Tendinous Be­ginning of this Muscle doth not only serve to support its Fleshy Body, but its Fibres Intersecting those of the Membranosus as they cover all the Muscles of the Tibia, do more ade­quately include them, whereby they are corroborated in their Action. When this Muscle Acts it pulls the Thigh directly Backwards.

Glutaeus Medius.Vesal. M. T. 10. σ. Bid. T. 72. D F. Spi­gel. T. 29. L. 4. L L.

This lies chiefly under the Tendi­nous beginning of the Former Muscle, and Arising Fleshy from almost the whole External part of the Spine of the Os Ilium (30), in its Descent be­comes Thicker and Fleshy, and is In­serted by a short strong Tendon to the Superior and External part of the Great Trochanter (40) in a Semicir­cular manner.

[Page 186]If the differing Series of Fibres in this Muscle are rightly considered, their Position will manifest they are not so Useful in Extending the Thigh as Authors would perswade us, but rather imployed in Turning it In­wards. This will plainly Appear if in the time of Dissection you give the Thigh that motion, you then may observe the Forepart of this Muscle notably relaxt. And in living Per­sons when the Thigh is turned in­wards, you may see it Tumified; or if in performing that Action with your own Thigh you lay your Thumb on this Muscle, you may feel it con­tract or Move under the Skin. Be­sides its being partly useful in Extend­ing the Thigh with the former Muscle, it is also imployed in divaricating the Legs, it co-operating with the Musculus Membranosus in that Action.

Glutaeus Minor,Vesal. M. T. 11. Z. Spigel. T. 30. L. 4. G G.

Lies totally under the Former Muscle, it being so much less than the Former, as the Former is the Precedent; It ariseth Semicir­cular, Broad and Fleshy, from the [Page 187] Dorsum Ilii (29); from hence itsFig. xviii. Fleshy Fibres descend to their partly Tendinous, and partly Fleshy Inser­tion like the Former, at the Superiour part of the Root of the great Trochan­ter (40).

The Fibres of this running Parallel, with those of the Former, assist it in all its Actions: Whatsoever Authors have said concerning an Obturator Fe­moris introrsum, we are well assured, that there is no other Muscle im­ployed in that Action, but the Fore­parts of these Two only. They also assist in rendering the Articulation of the Thigh Bone, with the Coxa, more Stable in standing Erect.

Pyriformis seu Iliacus Externus.Vesal. M. T. 10. b. Spigel. T. 29. Lib. 4. M.

It receives its First Name from its Figure, the Second from its Situation; its beginning is Round and Fleshy from the Inferiour and Internal part of the Os Sacram (35), where it re­spects the Pelvis of the Abdomen, andFig. xvii. descending obliquely in the great Sinus of the Os Ilium (35), above theFig. xviii. Acute Process of the Ischium, and joyning with the Glutaeus Medius, its [Page 188] Inserted by a Round Tendon to the Superiour part of the Root of the Great Trochanter (39). This movesFig. xviii▪ the Os Femoris somewhat Upwards, and turns it Outwards.

Marsupialis seu Bursalis.

So called from its Tendinous run­ning thorough (as it were) a Second Fleshy Beginning of it self, which Duplication represents a Purse; It is also called Obturator Internus from its Situation, and not from its Use, as some have imagined. It Ariseth Broad and Fleshy, from that part of the Os Ilium, Ischium (31), Pubis (33), and Ligament that is extended in the Great Foramen (36), of the two last named Bones internally, and march­ing Transversly in the Sinus of the Ischium, (fenced on each side by two Processes, the one Acute (32), the other Obtuse (31), where it is Externally Fleshy, but Internally it hath Three, sometimes Four Tendons passing in so many distinct Furrows in the said Sinus, like so many Cords in a Qadruple Pulley, where it meets with the other Fleshy Beginning, com­monly [Page 189] called its Marsupium, arising from the above-mentioned Acute and Obtuse Processes, which joyning with the said Tendons at their united In­sertion to the Superiour part of the Root of the Great Trochanter near the Implantation of the Former Muscle (39).Fig. xviii.

Riolan makes two Muscles of theAnthrop. [...]ib. v. [...]ap. 41. [...] Anatom. Cap. xix. Marsupium; which Error is taken no­tice of by * Marchette, who thinks the Marsupium a contrivance of Na­ture, whereby the Motion is confir­med, and the Subjacent Tendons defended from too great a pressure.

When this Muscle Acteth, its In­sertion is directed towards that part of the Ischium, over which its Ten­dons run after the manner of a Pulley, and the Os Femoris is thereby turned Outwards.

Quadratus Femoris.

So called from its Figure; it Ari­seth Broad and Fleshy from the Apo­physis of the Os Ischium (31), and pas­ses Transversly, with an equal Breadth and Thickness to its partly Fleshy and partly Tendinous Insertion at the [Page 190] Posteriour part of the Os Femoris, partly below the Great Trochanter.

This Assists the Former Muscle in turning the Thigh-Bone outwards. The next Muscle belonging to the Thigh, which appears as the Back part of it, lies Uppermost, is the largest Beginning of the Triceps, which, (contrary to others) we reckon the First Head of that Muscle.

Triceps.

So called from its Three Heads or Beginnings, the First and Largest of which Ariseth Broad and Fleshy from the Inferiour Edges and External parts of the Os Ischium and Pubis, where they are joyned to each other (33) lyingFig. xviii. between the Semitendinosus and Semi­membranosus, and that of the Gracilis, and Descending with an Oblique Or­der of Fleshy Fibres, is Inserted part­ly Tendinous and Fleshy near an Hands Length in Breadth to the Linea Aspera of the Thigh-Bone (37), that is immediately below the Insertion of the Former Muscle; Its Inferior part making a Strong Round Tendon In­serted into the Superior Part of the [Page 191] Internal and Lower Appendix of the Thigh-Bone (47). The Second HeadFig. xvii. or Beginning of this Muscle Ariseth Tendinous from the Os Pubis (38), but in its Descent soon becomes Fleshy, and joins with the Former, near to its Insertion to the Middle part of the Linea Aspera of the Thigh-Bone (37). The Third and Last Be­ginningFig. xviii. of this Muscle springeth from the Inferior part of the Os Pubis, be­tween the Origination of its Last De­scribed Head, and That of the Pecti­neus, and Descending obliquely joins with the First, near its Insertion to the Linea Aspera of the Thigh Bone, immediately above the Termination of the Second Head of this Muscle.

This moves the Thigh variously according to the Diversity of its Be­ginnings, so the First described part of it pulls the Thigh-Bone Upwards, Inwards, and somewhat Backwards; The Second and Third Beginnings of it Pulls it more Inwards, and turns it somewhat Outwards, as when we put our Legs a-cross each other.

Obturator Externus.

So called from its Situation, and Rotator Femoris Extrorsum from its Use; It hath a Large Fleshy Beginning from the External parts of the Os Ischium (39) and Pubis (38) and MembraneFig. xvii. that covers their Foramen (41) Ex­ternally, opposite to the Origination of the Marsupialis or Obturator Internus (already described) and passing trans­versly Backwards, lessens it self, and becomes Tendinous at its Insertion to the Root of the great Trochanter of the Thigh-bone (39) near the Ter­minationFig. xviii. of the Last named Muscle. This turns the Thigh Outwards.

Membranosus.

So called from the large Membra­nous Expansion it is Continuous with, inclosing all the Muscles of the Tibia and Tarsus; whence it is also called Fascia Lata: It hath an Acute Fleshy Beginning from the Forepart of the Spine of the Os Ilium (37) betweenFig. xvii. the Origination of the Sartorius and Tendinous Beginning of the Glutaeus Magnus, and being dilated to a Fleshy Belly which fills the Interstice made by the First of the two Last named Muscles and Upper part of the Rectus and Forepart of the Glutaeus Medius; [Page 194] in its Oblique Descent becomes Ten­dinous, Four Fingers breadth below the great Trochanter (45), whence itFig. xvii. passes directly over the Vastus Exter­nus to its proper Termination, at the Superior Appendix of the Fibula (53), but in its progress thither it is Con­joined with the Tendinous Expansion of the Glutaeus Magnus which Ariseth from the Spine of the Ileum (30) co­veringFig. xviii. the External part of the Glutaeus Medius and all the External Muscles of the Tibia as well as those of the Thigh-bone; and Descending over the Patella comprehends the Muscles of the Tarsus, and joins with the Liga­mentum Annulare, which retains the Tendons of the Toes and Foot: Un­less it may be supposed that the said Fascialata should end at the Lower part of the Thigh-Bone or Superior parts of the Tibia and Fibula, and that the last named Bones should give an Ori­gination to the Inferior part of the said Fascia, which seems to be a Matter more of Controversie than Use. When this Muscle Acteth, the Leg and Thigh are Drawn outwards; its Tendon be­ing joined with part of the Glutaeus Maximus, and having a different Se­ries [Page 195] of Fibres intersecting each other, do thereby, compose a strong Invo­lucrum, as well including all the Com­mon Muscles of the Leg, as covering the Proper; whereby they Corroborate them in their Action, as the Tendi­nous Expansion of the Biceps Cubiti doth Those of the Carpus and Fingers.

Sartorius.

It receives this Denomination from the Use Taylors make of it in bring­ing one Leg and Thigh over the other to sit cross Leg'd; It is also called Longissimus Femoris, it exceeding the rest of the Muscles of that Part in Length, and Fascialis from its passing over the Muscles of the Thigh and Leg like a Swathe. It Ariseth Sharp and Fleshy from the Forepart of the Spine of the Os Ilium (37) close byFig. xvii. the Former Muscle, and Descending obliquely inwards above the Musculus Rectus and Vastus Internus, and over part of the Triceps, of an equal Breadth and Thickness, meets with the Graci­lis below the Middle of the Thigh internally, and Descending with it becomes Tendinous in its Passage over [Page 196] the Internal and Inferior Head of the Thigh Bone, (under a strict Inclo­sure of the above described Fascia Lata) and is Inserted Four Fingers Breadth below the Superior part of the Tibia, internally (44). Its use is de­claredFig. xviii. above.

Gracilis.

So called from being the most slen­der of these Muscles; It Ariseth some­what Broad, partly Tendinous and partly Fleshy from the Os Pubis (38)Fig. xvii. internally, between the First and Se­cond described Heads of the Triceps, and in its Streight Descent in the In­side of the Thigh grows narrow, and becomes Tendinous a little above the Former Muscle, and is so Inserted (immediately beneath it) to the Tibia. (44.)Fig. xviii.

It Assisteth the Former and Follow­ing Muscles in bending the Thigh and Leg inwards.

Seminervosus seu Semitendinosus.

Which is so called from its being half Tendinous, and Nerve-like. It [Page 197] Ariseth partly Tendinous and partly Fleshy from the External part of the Protuberance of the Os Ischium (31),Fig. xviii. and presently being Dilated to a Large Fleshy Belly, becomes a Round Tendon in half its progress, which Descending over the Fleshy Belly of the Following Muscle, marcheth close by the Gasterocnemius on the Po­sterior part of the Superior Appendix of the Tibia, from whence it passes Forwards to its Insertion in the said Bone immediately Below the Termi­nation of the Former Muscle. (44.)

This with the Former Muscle Act­ing, Bend the Tibia directly Back­wards. Its Tendon together with the two Former and following Muscles make the Inward Hamstrings, as they are commonly called.

Semimembranosus.

So called from its being half Ten­dinous and Membrane-like; lying immediately under the former Muscle. It Ariseth Broad and Tendinous from the Protuberance of the Os Ischium, and in its Descent becomes broader, and in less than half its Progress be­gins [Page 198] to grow Fleshy, (where the Belly of the Former Muscle lessens it self) and is dilated into a Large and Fleshy Belly, lying under the Long Round Tendon of the Former, becoming a Short Thick Tendon Inserted to the superior part of the Upper Appendix of the Tibia Backwards. N. B. That the Fleshy Belly of the former Muscle is above; and That of This is Below, and their Tendons on the contrary.

Biceps.

Or Biceps Femoris to distinguish it from That of the Cubit: It having Two Heads, the superior and longest of which Ariseth with a Round Ten­don from the same Protuberance of the Ischium, as the Two Former, in its Descent becomes Large and Fleshy, and in above half its progress lessens it self again, where it is joined with its other Head, having a Broad, part­ly Tendinous and partly Fleshy Be­ginning from the Linea Aspera of the Os Femoris (37), immediately belowFig. xviii. the Termination of the Glutaeus Maxi­mus; it being thus united grows Ten­dinous, as it marcheth in a Channel [Page 199] on the External Appendix of the Os Femoris, becoming perfectly Tendi­nous at its Implantation to the Supe­rior Epiphysis of the Fibula. (47.)Fig. xviii.

Besides the Office commonly as­signed to this Muscle in Bending the Tibia together with the Two Former, it is likewise imployed in turning the Leg together with the Foot and Toes outwards, when we sit with the Knees Bended.

Popliteus.

By some called Subpopliteus, It Aris­eth with a Short, Strong Tendon from the External Head of the Infe­rior Appendix of the Os Femoris (42), from whence descending obliquely over the Juncture becomes Fleshy, and Expanding it self is so Inserted to the Superior part of the Tibia internally immediately below its Superior Ap­pendix (44). This doth not only Assist the Three Former Muscles in Bending the Tibia, but Antagonizeth the Precedent by turning the Foot and Toes outwards in that Position of the Leg as before Noted.

Rectus Femoris.

Is named from its streight Progress and Situation, it Ariseth Fleshy from a Tubercle of Os Ilium, that is in the Mid-way between the Forepart of its Spine and the Acetabulum †, fromFig. xvii. thence descending directly between the two following Muscles and over the Crureus, Its Fibres Externally Descend from a Middle Line ob­liquely Laterally; internally they run according to its Length, and become entirely Tendinous Four Fingers breadth above the Patella, where it is united with the Tendons of the three following Muscles, and Inserted to­gether with them at the Upper part of the Tibia. (50.)Fig. xvii.

Vastus Externus.

So called from its Magnitude and Situation, It Arises outwardly Ten­dinous, Inwardly Fleshy from the External part of the great Trochanter (45); and Linea Aspera of the Thigh­boneFig. xvii. Fig. xviii. (37), from whence its Fibres Descend Obliquely Forwards, and on [Page 201] the contrary become outwardly Fleshy and Tendinous Internally, and so soon as They meet with the Tendon of the Former Muscle, grow per­fectly Tendinous, and join with it and that of the two Following.

Vastus Internus.

This like the Former hath its De­nomination from its Situation and Magnitude; Its Beginning is Large, partly Tendinous, and partly Fleshy; it being continued from the Linea As­pera on the Back part of the Thigh­bone (37), from immediately belowFig. xviii. the Lesser Trochanter, till within Three Fingers Breadth above the Inferior Appendix of the said Bone Internally Laterally; from hence its Fleshy Fibres Descend obliquely outwards in an almost Semicircular manner, and on a sudden (like the Former Muscles) ceasing to be Fleshy, its Tendon is United with that of the Rectus, toge­ther with the Former and following Muscles, and Inserted with them.

Crureus seu Femoreus.Vesal. M. T. 5. II. Spigel. T. 35. L. 4. KK.

So called from its Situation on the Bone of the Thigh, like the Musculus Brachiaeus, on that of the Arm; Its Origination is Large and Fleshy, be­ing continued from between the Greater and Lesser Trochanter of the Thigh-bone Forwards (42), to itsFig. xvii▪ Lower part, that is Immediately a­bove its Inferior Appendix, Its Fleshy Fibres descending directly, and be­come perfectly Tendinous a little be­low the Upper part of the Tendon of the Rectus, where it joins with it, and the Tendons of the Two Last Describ­ed Muscles, which passes over the Ex­ternal part of the Patella, (or on each side of it) and is Inserted to a Promi­nence at the Superior and Forepart of the Tibia. (50.)

These Four Muscles last treated of, viz. Rectus Vastus Externus, Vastus Internus, and Crureus, may be esteemed One, in regard they make but one Ten­don at their Insertion, and serve for the same Use in Extending the Tibia, or Leg, however they are divided in­to several Bodies, and one of them is [Page 203] Inclosed on all sides by the Fascia Lata, namely the Rectus, and in themselves have a Multiform Series of Fleshy Fibres, whereby they are rendred capable of Performing their Office with greater strength, which is abso­lutely necessary not only in Running, Walking, Leaping, &c. but in Stand­ing to keep the Body Erect, by op­posing that Flexure at the Knee, which must otherwise necessarily happen through the superincumbent Pressure. For this reason likewise we find these Extending Muscles in so great a proportion Larger than their Antagonists the Benders, which ap­peared by their Weight, when at the Request of my very good Friend Dr. Brown, (now Reader on the Mus­cular Dissections at Chyrurgeons-Hall) these Extending Muscles were weigh­ed, and their Antagonists the Benders in the same Body, whereby we found the Former exceeded the Latter, two Pounds wanting an Ounce; The For­mer, namely the Extensores, weighing Three Pounds six Ounces, and their Antagonists the Latter but One Pound seven Ounces. Should it be inquired, (since it is so Apparently necessary in [Page 205] most, if not All Motions of the whole Body that the Leg ought to be Ex­tended with great Force, it being Bended to support its own weight only) Why the Muscles employed in that Action should all Terminate in one Tendon, when their Antago­nists the Benders have Divers Inserted on both sides the Bones of the Leg; whereby They have a greater advan­tage in doing their office than that one single Insertion of the Extenders? It may be Answered, that such a Stru­cture is not only for the Beauty of the Part, but it is necessary that the Tendons of the Former should be United into One near their Insertions, and that a Bony Body, such as is the Patella, should be placed on the Arti­culation of the Thigh-bone with the Leg to defend it from being prest on, in going down steep places, which could not have been done, had They been divided and Inserted on each side of the Bones of the Leg like the Flexors, which is a Stupendious De­vice in Nature.

Gasterocnemius Externus, it. Gemellus.Vesal. M. T. 9. [...]. Spigel. T. 38. L. 4. Fig. i. GG DE. Bid. T. 83. E.

So called because (with the Soleus or Internus of that name) it composes the Calf of the Leg: it is also called Gemellus from its being as it were [Page 206] double. It has two Distinct Fleshy Originations from the Superior and Hindmost parts of each Tubercle of the Lower Appendage of the Thigh­bone (42), which in their descent areFig. xviii. each dilated into two large Fleshy Bellies; The innermost of which is Thickest and Largest, having each a differing Series of Fleshy Fibres, and join to each other near where they make a Broad Strong Tendon, which nar­rowing it self joins with the great Tendon of the Gasterocnemius Internus, four Fingers breadth above its inser­tion to the Os Calcis. (49.)

Riolan asserts, with Vesalius, that inLib. v. Cap. 43. the two Beginnings of this Muscle there are two Ossicula sesamoidea, which we must acknowledge with Marchette have hitherto escaped our Observati­on, though its likely it may be so in Aged Bodies, as it appeared in a Sub­ject I lately Dissected on One Side only.

When this Muscle Acts the Foot is said to be Extended or Pulled Back­wards, which motion of it is very necessary in Walking, Running, Leap­ing, and standing on Tiptoe, &c. Hence it is those that Walk much have these Muscles Larger than others, [Page 207] through the frequent use of them, and amongst which those that carry Hea­vy burthens, and especially Sedans or Chairs in this Town; and Those who wear Low-heeled Shoes have these Muscles remarkably larger than Others.

Plantaris.Vesal. M. T. 13. Φ. Spigel. T. 38. [...] 4. Fig. 2. I [...]K.

So called from its Tendon expand­ed in the Planta Pedis like that of the Palmaris in the Palm of the Hand. It Arises Fleshy from the Superior and Back-part of the outermost Tubercle of the Lower Appendage of the Thigh­bone (42) immediately under the Ex­ternalFig. xviii. Beginning of the Former Muscle, and Descending Obliquely between it and the Following, soon becomes a Thin Flat Tendon, which passing out from between Their Fleshy Bellies descends internally laterally, by their great Tendon; and march­ing over the Os Calcis (49), expandsFig. xviii. it self on the Soal of the Foot, where it firmly adheres to the Fleshy Body of the Musculus Flexor Digitorum Per­foratus, and is Inserted on both sides the first Internode of each lesser Toe. The Action of this Muscle is very [Page 209] obscure, its Tendinous Expansion on the Bottom of the Foot being chiefly serviceable in defending the subjacent Muscles, Tendons, Nerves, and large Bloud Vessels, from being Comprest in Standing, Walking, &c. We have sometimes observed that the Fleshy Beginning and long Tendon of this Muscle is wanting.

Gasterocnemius Internus.Vesal. M. T. 14. [...]. Spigel. T. 38. L. 4. Fig. 2. MM. Bid. T. 84. F.

This is placed under the two former Muscles; It's also called Soleus from its Figure; resembling a Sole-Fish: its External Fleshy part is co­vered with a Transparent Tendinous expansion, which makes it appear of a livid Colour. Its Beginning is partly Tendinous, but chiefly Fleshy from the hindmost part of the upper Appendix of the Fibula (47), andFig. xviii. Back-part of the Tibia (45), that is below the Insertion of the Subpopliteus, and increasing to a large Fleshy Belly composed of Various Orders of Fleshy Fibres, some of them underneath aptly expressing the Figure of the top of a Feather, whose Stamina here being Tendinous join with the great Tendon [Page 209] which is about four Fingers breadth in length, and Inserted to the Superior and Hindmost part of the Os Calcis. Fig. xviii. (49.)

The Foot, together with the Toes, being as it were a Leaver to the whole Body, ought therefore to be attended with Muscles of great strength to Ex­tend it, wherefore we find these Muscles so much to exceed their An­tagonist the Tibaeus Anticus, as well in the advantageous construction of their differing Series of Fleshy Fibres, as their Magnitude and Insertion at the extremity of the Os Calcis: where­by they are not only rendered ser­viceable in Walking, Running, Leap­ing, &c. but do also support the Tibiae in standing, lest the superincumbent Pressure of the Weight of the Body should make them incline forwards at their Articulations with the Talus.

Tibialis Anticus.Vesal. M. T. i. Z. Spigel. T. 40. NNO. Fig. 2. Bid. T. 80. D. T. 81. E.

So called from its situation on the Forepart of the Tibia, its also by Spi­gelius called Musculus Catenae, because when it is divided the Patient is forced to use a Sling to support the [Page 210] Foot in Walking. Its Origination is Fleshy from the Lower part of the Su­perior Appendage of the Tibia (50)Fig. xvii. between its Prominence, where the great Tendon of all the Extending Muscles of the Leg is Inserted, and the Origination of the Musculus Ex­tensor Magnus Digitorum Pedis: it also continues a Disgregated Fleshy Ori­gination for near two Thirds of the Superior part of the said Tibia Exter­nally lateral next the Fibula (52); which Composing a Fleshy Belly les­sens it self in Half its Progress, and growing into a Strong and somewhat Round Tendon descending obliquely over the Inferior Part of the said Tibia, and under the Annular Ligament, is Inserted to the inside of the Os F. xviii. 53. Cu­neiforme Majus (57) that sustains the Os Metatarsi Pollicis.

This pulls the Foot Upwards and Forwards Directly.

Peroneus primus.Vesal. M. T. i. [...]. Spigel. T. 40. F. 2. C D. Bid. T. 81. E. 82. C.

By some it is called Longus it be­ing the First that offers it self to view; and the longest Muscle seated on the Fibula or Os Perone (56). ItFig. xviii▪ [Page 211] Arises Externally Tendinous, and Fleshy Internally from above half the Superior part of the said Bone, and marching somewhat Backwards becomes a Strong, Flat Tendon, Four Fingers breadth in Length above the Inferior Appendage of the said Fibula called Malleolus Externus (48), passingFig. xviii. behind which in a Channel like a Rope in a Pully, and from thence being in­flected forwards together with the Tendon of the following Muscle, they pass under an imbanding Liga­ment as they run over the Os Calcis, but this Tendon declining from its companion marches over the F. xvii. 60. Os Cu­boides (51) under the Musculus Ab­ductor Minimi Digiti, and over the Ossa Cuneformia in the bottom of the Foot, and under the Tendons and Muscles Bending the Toes, and is In­serted to the Superior and Hindmost part of the Os Metatarsi of the Great Toe.

The Tendon of this Muscle being conveyed over the Hindmost part of the Malleolus Externus (44), as on aFig. xviii. Pully, is an elegant contrivance in Nature, whereby the Ball of the great Toe (as that part is commonly [Page 205] [...] [Page 206] [...] [Page 206] [...] [Page 207] [...] [Page 209] [...] [Page 209] [...] [Page 210] [...] [Page 211] [...] [Page 212] called to which It is Inserted) is directed towards a Perpendicular bearing of the Weight of the Body on the Leg in standing on Tip­toe by pulling the Foot and Toes somewhat outwards.

Peroneus Secundus.Visal. M. T. 6. Ψ. Spigel. T. 40. L. 4. F. 2. EEF. Bid. T. 82. B.

By some called Semi-fibulaeus: It has an Acute Fleshy beginning above the Middle of the External part of the Fibula (46) under the Fleshy Bel­lyFig. xviii. of the Former Muscle, it also continues its Fleshy Beginning from the Posterior Sharp Edge of the said Fibula, and Becoming a Fleshy Belly grows Tendinous as it runs under the Malleolus Externus (48) together withFig. xviii. the Tendon of the former Muscle, and is inserted to the Superior and External part of the Os Metatarsi of the Little Toe.

The proper Action of this Muscle is to pull the Foot and Toes out­wards.

Tibialis Posticus.Bid. T. 85. G. Vesal. M. T. 15. D E.

This being placed on the Back part of the Tibia, is also called Musculus Nauticus, because Mariners chiefly use it in climbing up the Masts of their Ships. It lies partly under the Flexor tertii internodii Pollicis, which Muscle must be partly raised, together with the Flexor tertii internodii Digitorum Pe­dis, before we can have a clear sight of it. It appears Biventral, Arising partly Tendinous and partly Fleshy from the Superior and Back-part of the Fibula (47), as also from the Li­gamentFig. xviii. that is continued between the said Bone and the Tibia (45), in near half its progress it becomes less, and grows Fleshy again, and making a Strong Round Tendon which runs in a Sinus on the back-part of the lower Appendage of the Tibia called the Malleolus Internus (51) under an An­nularFig. xvii. Ligament, and is inserted to the Os Naviculare (54) internally and la­terally.Fig. xviii. Fig. xvii. 56.

This draws the Foot upwards and inwards.

Extensor Pollicis Longus.Vesal. M. T. 4. 14. Spigel. T. 40. L. 4. F. 2. L. Bid. T. 81. H. T. 82. G.

This Muscle doth not Arise as most Describe it, from the Tibia, or [Page 215] from the Ligament between it and the Fibula. It's Beginning is Large and Fleshy from the Fore-part of the Fibula (52) from immediately be­lowFig. xvii. its superior Appendix, to Four Fingers Breadth above the Inferior one, and Descending under the Liga­mentum Annulare of the Tarsus, be­tween the Tendon of the Tibialis Anticus and those Tendons of Exten­sor Pedis Longus, and marching along the superior part of the Foot, Is In­serted to the Upper part of the Se­cond Bone of the Great Toe (63). Its Name Intimates its Use.

Extensor Pollicis Brevis.Bid. T. 82. not letter'd.

Though this Muscle is not men­tioned by Anatomists, yet we con­stantly observe it in Dissection, It hath been rather taken for part of the Extensor Digitorum Brevis, but we fre­quently find it Distinct.

It Ariseth Fleshy from the Forepart of the Os Calcis (61), being Dilated into a Belly, soon becomes a Long, Slender Tendon, passing obliquely over the upper part of the Foot, and is Inserted to the superior part of the [Page 216] Second Bone of the Great Toe, which it Extends or Pulls Up­wards.

Flexor Pollucis Longus.Bid. T. 84. not let­ter'd. TT. 85. K.

This is a direct Antagonist to the Extensor Longus, It Arises opposite to it from the Back-part of the Fibula (46) with a double Order of FleshyFig. xviii. Fibres, running to a Middle Tendon, (like the Flexor tertii internodii Pollicis Manus above) which ceaseth to be Fleshy as it passes over the Juncture, and runs through a Channel on the Internal part of the Os Calcis (49) under the Tendon of the Musculus Flexor Digitorum Longus Perforans over the Following Muscle, and is Inserted to the Upper End of the Second Bone of the Great Toe.

Flexor Pollicis Brevis.Bid. T. 86. F. i. not let­ter'd.

Is Short, Thick, and Fleshy, seem­ingly divided into Two Muscles by the Tendon of the Former passing over it. It Ariseth from the superior part of the Os Cuneforme medium (58),Fig. xvii. and running over the Termination of [Page 217] the Musculus Peroneus, is Implanted into the Ossa Sesamoidea of the Great Toe, who are likewise Tied to the superior part of the Second Bone of the said Toe, which it Bends.

Abductor Pollicis.Bid. T. 86. F. 2. C C.

This Ariseth Fleshy from the Os Calcis internally Laterally, in half its Progress becoming Tendinous, it joins with another Fleshy Beginning, spring­ing from the Os Cuneforme majus (57)Fig. xvii. that sustains the Os Metatarsi of the Great Toe; both which making one Tendon, are Inserted to the External part of the Os Sesamoides of the Great Toe Laterally.

This pulls the Great Toe from the rest.

Adductor Pollicis.Bid. T. 86. F. 2. D.

This is Described and Figured by C. xix. Veslingius, It is also mentioned by Marchette, It ariseth partly Tendinous and partly Fleshy from the Inferior parts of the Os Cuneforme Tertium (59), and Dilating it self to a Fleshy Belly, marcheth obliquely in the bottom of [Page 216] [...] [Page 217] [...] [Page 218] the Foot, and becomes less and Ten­dinous at its Insertion to the Internal part of the Ossa Sesamoidea of the Great Toe laterally, opposite to the Termination of the Former.

This Brings the Great Toe nearer the rest.

Extensor Digitorum Pedis Longus.Vesal. M. T. i. α β. Bid. T. 82. D.

This hath an Acute Fleshy Begin­ning Externally from the Inferior part of the Upper Appendix of the Tibia (50) next the Fibula (53), as also aFig. xvii. Long Fleshy one from the Superior part of the last named Bone, and lessening it self in half its Descent on the Leg, it joins with a Second, Broad, Disgregated Fleshy Beginning, continued for near half the Inferior part of the said Fibula, where Descend­ing under the Ligamentum Annulare of the Talus, it is divided into Five Tendons, Four of which are Inserted to the Third Bones of all the Lesser Toes; The Fifth to the superior part of the Os Metatarsi of the Little Toe, which part of it Vesalius makes hisLib. ii. Cap. lx. Ninth Muscle belonging to the Foot.

Extensor Digitorum Brevis.Vesal. M. T. 6. Ω. Bidloo T. 82. F.

This is a short Fleshy Muscle ly­ing under the Tendon of the Former on the Foot. It Ariseth Fleshy from the External and Forepart of the Os Calcis (61), soon Dilating it self to a [Page 220] Fleshy Belly, which being divided into Four Fleshy Portions becomes so many Tendons, passing over the Up­per part of the Foot, and making Acute Angles with the Tendons of the Former Muscle as they run over the First Internode of each Lesser Toe to their Insertions at the superior parts of their Second.

Perforatus.Vesal. M. T. 14. ☉. Spigel. T. 42. F. 2. C. D. Bid. T. 85. I.

So called because its Tendons are Perforated like Those of the Fingers. It is also called Flexor Secundi Inter­nodii Digitorum Pedis, from its Use and Sublimis from its Situation, It springeth from the Inferior and Inter­nal part of the Os Calcis (49) be­tweenFig. xviii. the Musculi Abductores of the Greater and Lesser Toes. Dilating it self to a Fleshy Belly after it hath passed the middle of the Planta Pedis, it is divided into four Fleshy Portions, which become so many Tendons, and are divided near their Terminations to Admit the Tendons of the follow­ing Muscle to pass through them to their Insertions; These being United again, pass underneath them to their [Page 221] Implantations at the Upper part of the Second Bone of each Lesser Toe.

Perforans.Vesal. M. T. 15. P. Bid. T. 85. H.

So called because its Tendons run through the Fissures in the Tendons of the Former, It is also called Flexor tertii Internodii Digitorum Pedis from its Use. It hath an Acute Fleshy Ori­gination from the Back-part of the Tibia (45) immediately under theFig. xviii. Musculus subpoplitaeus, having a double order of Fibres united in a middle Tendon like the Flexor Pollicis Longus, but ceaseth to be Fleshy as it passeth behind the Malleolus Internus, and run­ning in a Channel over the Internal part of the Os Calcis (49) under it, Imbanding Liguments in half its Pro­gress through the Sole of the Foot, it is divided into Four Tendons which march thorow the perforations of the Tendons of the Former Muscle, and are Inserted to the Third Bone of every Lesser Toe.

Lumbricales.Spigel. T. 42. F. 3. F F. Bid. T. 86. FF. Bid. T. 86. F. i. FF.

So called from their Figure like those of the Hand, and though Anatomists have generally described them Arising from the Tendons of the last treated of Muscle, yet we rather think the Carnea massain the Planta Pedis, is their true Origin, It springing from the Internal part of the Os Calcis, and becoming Tendinous joins with the Tendons of the Former Muscle, in the middle of the Sole of the Foot, Then dividing it self into Four (as it were) distinct Fleshy Muscles, they all become Ten­dinous at their Insertions to the In­ternal parts of each Lesser Toe Late­rally next the Great Toe.

Abductor Minimi Digiti.Spigel. T. 42. Lib. 4. F. 3. K M. Bid. T. 86. F. 2. B.

This Ariseth outwardly Tendinous, inwardly Fleshy from the External part of the Os Calcis (49), becomingFig. xviii. Tendinous in half its progress on the outside of the Foot, it joins with the other Fleshy part of this Muscle A­rising Fleshy from the Outside of the Os Metatarsi of the Little Toe (57), [Page 223] and making one Tendon at its Inser­tion to the Upper part of the First Bone of the Little Toe Externally La­terally.

Transversalis Pedis. [...]id. T. 16. F. 2. [...].

So called from its Transverse Situa­tion. It Ariseth Tendinous from the Internal Os Sesamoides of the Great Toe, and becoming a Fleshy Belly in its Progress over the First Internodes of the two next Toes, it is Lessened at its Insertion to the Inferior part of that Metatarsal Bone which supports that Toe next the Lesser.

Its Use is to bring the Lesser Toe towards the Greater.

To this may be Added a Flexor ☞. Primi Ossis minimi Digiti, though some reckon it amongst the following Inte­rossei, yet its situation doth not de­serve that Name. It Ariseth Fleshy from the Superior part of the Os Me­tatarsi Minimi Digiti, and passes di­rectly to its Insertion in the First Bone of the Lesser Toe. In the Tendon of this and the Interossei, the Ossa Sesa­moidea of the Lesser Toes are enter­tained.

Interossei Pedis.Spigel. T. 43. L. 4. F. 2. D D C C. Bid. T. 86. F. 3. AAA.

These are reckoned to be Seven in Number, They derive their Names from their Situation, and may each deserve a Proper Appellation from their Use. The First may be called an Adductor Minimi Digiti. The Se­cond, which is the Largest, draws the next Toe towards the Lesser, and may be called Abductor A [...]ricularius. The Third Antagnises the Former, and is an Abductor of that Toe. The Fourth may be called Abductor Medii Digiti. The Fifth is an Adductor of the same. The Sixth is an Adductor, and Seventh Abductor Indicis Pedis. All these Arise Fleshy from the Superior part of the Ossa Metatarsi of the Lesser Toes (62),Fig. xvii. and becoming Bellied grow Tendi­nous at their Insertions to the First Internode of each lesser Toe laterally.