MYOLOGY OF THE ORNITHORIIYNCIIUS. 



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joint behind to be inserted, chiefly fleshy, into the posterior tubercle 

 upon the head of the humerus. It rotates the bone inwards, feebly 

 counteracting the two preceding muscles. 



Teres major. — Double ; both portions of great size, and perfectly 

 distinct. The lower, or teres major proper, arises fleshy from the 

 posterior extremity of the scapula for about one-third of an inch ; it 

 lies at first upon the serratus magnus, and then along the superior 

 border of the latissimus, forming a great pyramidal muscle running 

 between the last and the upper teres, rapidly narrowing to a rather 

 long, stout, flattish tendon that passes behind (mesiad of) the scapular 

 head of the triceps, to be inserted in the posterior ridge of the hume- 

 rus, one-half inch or more above the insertion of the latissimus. On 

 its deep surface muscular fibres reach nearly to its insertion; on the 

 superficial aspect, the large glistening tendon radiates nearly half way 

 to origin. The upper portion is still larger, and has more extensive 

 and complicated Origin from both " sides " of the scapula, which is 

 thus, as it were, embraced by the muscle. The outer origin is from the 

 postero-external aspect of the scapula, from the origin of the lower 

 teres to that of the scapular head of the triceps ; the inner origin is 

 thinner and more extensive and fleshy, from the whole surface of 

 bone between the insertions of the two digitate sets of levatores scap- 

 ulae. The muscle is pyramidal in shape, like, and with the general 

 aspect of, the preceding, and with precisely similar tendinous arrange- 

 ment. But it is inserted much higher up, in immediate relation with 

 the shoulder-joint, into the posterior tubercle of the humerus, along- 

 side the insertion of the muscle above called subscapularis. N. B. 

 Its tendon contains an articular sesamoid bone. 



Two perfectly distinct muscles besides the one above called "ante- 

 rior deltoid" proceed from the coracoid apparatus to the humerus; 

 they have together been considered as coraco-brachialis, but the 

 name is properly applicable to only one of them. 



Coraco-brachialis proper. — This is the posterior, and the longer and 

 slenderer of the two. It arises by a very short tendon in common 

 with the larger moiety of the biceps, from the sternal extremity of 

 the coracoid ; quickly enlarges to form a flattened-fusiform muscular 

 belly, representing the postero-internal margin of the arm ; it is over- 

 laid by the greater moiety of the biceps, itself overlying at first, the 

 muscle next below described, and afterwards the tendon of the la- 

 tissimns, which it crosses at right angles. Its insertion is fleshy and 

 with a very short tendon, into the lower part of the entocondylar 

 ridge of the humerus, nearly opposite the foramen : its outer surface 

 of insertion is in relation with the pronator radii teres. 



Epicoraco-brachialis. — Much larger than the other, and with differ- 

 ent origin, course, relations and insertion ; lying partly upon and 



