140 COUES, 



of the muscle runs transversely; the anterior border folds around the 

 side of the neck parallel and in apposition with the s. -mastoid; the in- 

 sertion is partly fleshy, partly tendinous, into the scapular spine, and 

 border of episternal bar, as far to the front as the insertion of the deep 

 s. -mastoid. The posterior part, arises from the lOth-llth ribs by two 

 fleshy digit ations situate respectively 1' and U' from the back-bone, 

 and from a broad, oval, dorsal aponeurosis common to it and its 

 fellow. The muscle has the form of a narrow scalene triangle; 

 its lower border approaches the spine about the middle of the back, 

 and is there contiguous with its fellow; the anterior border passes 

 straight up the side of the chest, lying upon the latissimus, past the 

 back of the arm ; the acute apex is inserted by a very short, thick 

 tendon into the end of the scapular spine, in connection with the 

 posterior corner of the insertion of the anterior trapezius, and of the 

 deltoid behind — the latter curving down in front of the arm, which 

 is thus set in a deep recess betwixt these two muscles. Under this 

 portion of the trapezius, in the deep hollow of the back between the 

 shoulders, the large gland lies embedded in copious lax areolar tissue. 

 When the two parts of the trapezius act together the effect is much 

 the same as if they were not disjoined ; the special effect of their dis- 

 sentaneous action, if they have such, is not so evident. 



Bhomboideus. — Single; of large size, and thick. It arises in appo- 

 sition with its fellow along the median line of the neck behind (dis- 

 position above, and cranial attachment,. if any, not seen) ; the lower 

 border passes transversely to the scapula, and a little downward; the 

 insertion, broad and fleshy, is into the apex behind, and about §' along 

 the posterior border of, the scapula. Has the usual action. 



Costo-scapularis ; serratus magnus s. anticvs. — Perfectly distinct from 

 the cervico-scapular plane, from which it is separated by a triangular 

 interval an inch wide in front, narrowing behind as the two muscles 

 mutually approach towards the apex of the scapula. The muscle is 

 unusually small, consisting of only three short digitations from lst-3d 

 ribs, rapidly lengthening from first to third, the last almost perfectly 

 continuous with the first slip from the obliquus abdominis ; the three 

 fascicles remain distinct near to their insertion, which is by a short 

 terete tendon into the very tip of the scapula. Has the usual action. 



Pectoralis minor? — Besides the serratus, another plane of muscle 

 connects the shoulder apparatus with the top of the thorax; it has 

 somewhat the situation and relations of an 'intercostal' betwixt first 

 rib and the bones above. It is divisible into two parts. One of these, 

 costo-coracoicl, is larger and thicker than the other; it arises from the 

 first rib, from the origin of the serratus magnus slip to the sternal 

 articulation, and is inserted mainly into the base and inner surface 

 of the coracoid. A smaller, thinner plane, manubrio-epicoracoid. 



