M. BPITROCHLEA.RIS. 259 



of its head ; associated at its origin with the subscapularis, and at 

 its insertion with the latissimus. 



Dissection. — Both borders of the muscle have been indicated 

 during the examination of the subscapularis and latissimus. Con- 

 nect them at the point of junction of the M. teres with the last named 

 muscle. The scapular part of the muscle may be dissected from its 

 attachment along the border of the scapula, but the humeral part — 

 together with the humeral part of the latissimus — can be reflected 

 with ease. 



Origin. — By fleshy fibers, from all but the glenoid sixth of a 

 shallow groove along the glenoid border of the scapula ; this groove 

 intervenes between the true glenoid border and the marked ridge 

 upon the subscapular surface which runs nearly parallel with it at 

 a distance of 4-5 mm. It arises also from the aponeurotic septum 

 between it and the subscapularis. 



Insertion. — This has been described in connection with the 

 M. latissimus (§ 635). 



M. EPITROCHLEAEIS. 



§ 681. Synonymy. — The dorso-epitrocMien of monkeys, and, by exception, of man, Q., 

 A, I, 207; " triceps-interne," S.-D., A, II, 348; dorso-epitroehlear, Miv., A, 137. 



Figures. — Ectal aspect (72, left side) ; distal end, reflected (72, right side) ; both 

 ends (75). 



Posture. — Let the arm rest upon its cephalic surface, with the 

 olecranon and the gleno-vertebral angle of the scapula toward the 

 dissector. The muscle was exposed during the dissection of the 

 pecto-antebracMalis and clavo-deltoideus. 



General Description. — A thin ribbon, from the vertebral bor- 

 der of the latissimus to the caudal border of the olecranon process 

 of the ulna. 



Dissection. — The ventral border was indicated in the dissection 

 of the pecto-antebracMalis ; the dorsal border may be seen if the 

 latissimus is drawn toward the head of the humerus. Both borders 

 should be freed from connective tissue and thin fascia ; then the 

 muscle may be divided at its middle. 



Origin. — Variable and ill defined. By fleshy fibers from the 

 ventral border of the latissimus^ just opposite the oblique line of 

 union of the latter muscle with the teres, and close to the place of 

 reception of the dermo-humeralis ; occasionally some of the fibers 

 arise from the latter muscle. 



