8 PROCEEDINGS OF THE NATIONAL MUSEUM voi,. SO 



nerve passed entirely deep to the muscle, and insertion was upon 

 the shaft from a point immediately beyond the latissimus tendon 

 to a situation upon the epicondyloid ridge just short of the entepi- 

 condylar foramen, and hence not to the epicondyle proper. 



M. hrachialis, partes lateralis et medialis. — The brachialis was 

 primitively and entirely separable throughout its length. The more 

 medial head originated fleshily from the humeral shaft just beyond 

 the pectoralis insertion, while origin of the lateral head was chiefly 

 tendinous from the extreme proximal part of the surgical neck. 

 Insertion was by two tendons upon the ulna. 



In Tars^ius saltator the brachialis could not be clearly separated 

 into two parts, there being only slight indications of a longitudinal 

 splitting. The insertion was by a single tendon upon the ulna. 



M. epitrochleo-anooneus. — This small slip, innervated by the ulnar 

 nerve, arose from the epicondyloid ridge below the level of the ente- 

 picondylar foramen, and its conformation was such that it would be 

 extremely easy to mistake it for a condylar extension of the coraco- 

 brachialis medius. 



Didelphis virginiana. — Johns Hopkins Anat. No. 117, male, 

 with humeral length of 57 mm. ; left side. An opossum was dissected 

 in order to present the arrangement of the brachial flexors in a 

 primitive marsupial. 



M. biceps brachii, capita longum et breve. — The long head arose 

 from the supraglenoid border of the scapula by a tendon that passed 

 through the bicipital groove and that seemed to be at least partially 

 within the capsule of the shoulder joint. The short head took origin, 

 by fibers partly muscular and partly tendinous, from the inner side 

 of the tip of the coracoid process. This head crossed in front of the 

 caput longum at the elbow and inserted upon the radius by a strong- 

 tendon. The long head, passing inward, united with the brachialis 

 to insert by a tendon upon the ulna. It is thus apparent that the two 

 heads were separate for their entire length. There was no lacertus 

 fibrosus. 



M. ccyracohrachialis profundus. — Since the medius division was 

 entirely absent, the coracobrachialis was represented only by the 

 short or profundus element. This was a large and well-developed 

 muscle. Its origin was by a tendon from the inner and under aspects 

 of the coracoid process. Broadening and developing muscle fibers, 

 it inserted upon the medial side of the neck of the humerus above and 

 behind the tendons of the teres major and latissimus dorsi. 



M. hrachialis. — This arose strongly from the outer side of the 

 humerus as high as the level of the latissimus insertion and from 



