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 r O M Y. 193 Part II. A N A fort of trituration, of great importance to the animal ceThe fuperior extremity of each mufcle is fixed to a conomy. They Comprefs the abdomen, in order to clear part of the lower extremity of the fternum, to the three it of what ought to pafs off by tbe natural outlets; to lowed true ribs, and to the firft falfe rib, by the fame relieve the ftojnach,. by vomiting, from whatever might number of digitations, of which that which is fartheft be hurtful to it; and, laftly, to drive out, by a violent from the ftemum is the broadeft. whatever may incommode the organs containThe body of the mufck lies in the vagina, formed by expiration, in the thorax. t-He aponeurofis of the broad mufcles of the abdomen. ed The mufculi refli ferve to fupport the trunk of the Exteriorly, it is divided into feveral portions, refembling body when inclined backward, and to bend or bring it diilinft mufcles placed endways, by tranfverfe tendons, forward again; to raife the body up when lying ; and, termed enervations, which commonly are all above the laftly, climb. umbilicus, very feldom below it, and they adhere very The topyramidales feem only to aflift the adtion of the clofe to the vagina. when we confider the oblique direflion The lower extremity of this mufcle is narrower than refti;theirthough, fibres toward the liftea alba, there may be fome the upper, and ends in a thin tendon fixed in the inter- ofreafon to think that they comprefs the bladder, efpecially nal labium of the upper edge of the os pubis, near the when very full of urine. fymphyfis, and there it touches the tendon of the other The tranfverfales feem to have no other ufe than that jredus. of bracing or girding the abdomen in different degrees. MUSCULI PYRAMIDALES. At the lower part of the red'd, we meet commonly Sect. III. ’The Muscles which move the with two fmall mufcles, which at firft feem to be a porBones of the Shoulder upon the Trunk, tion or appendix of the former. They are named pyramidales from their figure; and by Fallopius, fuccentuTRAPEZIUS. riati. At the lower extremity, they are broad and thick, The trapezius is a large, broad, thin, fleftiy plane, fifuated between the occiput and lower part of the back, being there fixed to the upper edge of the offa pubis, immediately before the redd. They decreafe gradually and from thence extending to the Ihoulder, in the figure in breadth and thicknefs as they afcend, and end by a of a large irregular fquare. From this figure the ancient point in the Imea alba, a little way below the umbilicus. Greeks took its name, and, together with the trapezius of the other fide, it forms a kind of lozenge. Above, it is fixed in the fuperior tranfverfe line of TRANSVERSALES. the os occipitis, by a thin feries' of fleftiy fibres, reachThe tranfverfe mufcles are nearly of the fame breadth ing to the mufculus occipitalis,, and appearing to cover with the obliques. Each of them is fixed to the ribs a- that mufcle by a kind of aponeurofis. Behind, it is fixbove.; below, to the os ilium, and ligamentum Fallo- ed to the five fuperior fpinal apophyfes of the neck, by pii; before, to the linea alba; and behind, to the ver- means of the pofterior cervical ligament, and immediatetebras. ly to the extremities-of the two loweft fpinal apophyfes The upper part of this rnufcle is fixed to the lower of the neck, and of all thofe of the back. part of the inner furface of the cartilages of the two This mufcle covers immediately the fplenius or maftoilowed true ribs, and of all the five falfe ribs, by flelhy daeus fuperior, part of the complexus major, the anguladigitations, the fibres of which run more or lefs tranf- ris,-rhomboides, and part of the latiflimus dorfi. verftly tov/ard the linea alba, at fome diftance from which they become tendinous. RHOMB 01 DES. The middle part is fixed to the three firfl: vertebrae of the loins, by a double aponeurofis, or two tendinous This mufcle is a thin, broad, and obliquely fquare planes, one internal or anterior, the other external or fleftiy plane, fituated between the bafis of the fcapula and pdfterior. • the fpina dorfi ; and it is from its figure that-it has been The inferior part of this mufcle is fixed by an infer- termed rhomboides. tion wholly fleftiy to the internal labium of the crifta of- It may be divided into two portions, one fuperior, the fis ilium, and to a great part of the ligamentum Fallopii. other inferior, which fometimes appear feparate. The From thence many of its fibres run towards the linea al- fuperior portion is fixed, by an infertion wholly flefhy, ia, the reft to the os pubis, all of them becoming more in the two or three loweft fpinal apophyfes of the neck, or lefs tendinous before their infertion. and partly in the pofterior cervical ligament. The inferior portion is fixed, by a tendinous plane, in the three four uppermoft fpinal apophyfes of the back. USES of the ABDOMINAL MUSCLES. or Thefe two portions, of which the inferior is by much The common ufes are, to fuftain the vifcera of the ab- the broadeft, being united, are inferred in the edge of domen, and to counterbalance the perpetual motions of the bafis fcapulae, from the fmall triangular fpace to the •ordinary refpiration, and thereby gently and continually inferior angle, the fuperior portion covering a fmall part to *<51 on the vifcera; which aftion may be reckoned a of the infertion of the angularis. This Vol. I. No. 9. 3