ART. 13 BRACHIAL FLEXOES IN" PRIMATES HOWELL AND STRAUS 



short distance of insertion. The short head was more completely 

 integral with the coracobrachialis origin than in Pan or man, many 

 of its deeper fibers arising directly from the coracobrachialis tendon 

 and the two not separating completely until after passing the latis- 

 simus tendon. There was no lacertus fibrosus. 



M. coracobrachialis^ partes profunda et media. — The pars pro- 

 funda was entirely distinct from the media, arising fleshily, mostly 

 from the posterior (medial) border of the common coracoid tendon 

 but also partly deep to the tendon and from the coracoid proper. It 

 curved around deep to the tendon to insert upon the surgical neck 

 of the humerus, mostly proximal to the latissimus insertion, although 

 a few fibers overlapped the latter for a couple of millimeters, both 

 superficial and deep to its proximal border. The pars media was 

 very slender and small, with the musculocutaneous nerve passing 

 between all of it and the bone. Its fibers arose from an aponeurosis 

 upon its deep surface, which in turn was a continuation of the cora- 

 coid tendon, and it inserted upon an area but 10 mm. long beginning 

 23 mm. below the latissimus tendon. 



M. hrachialis. — This muscle was not longitudinally divisible and 

 was relatively much less robust than in Pan. Origin began from an 

 oblique line that extended from above the termination of the deltoid 

 on the lateral aspect of the arm to a point well below the deltoid on 

 the medial aspect, and thence straight to the fieshy insertion, which 

 was partly upon the joint capsule but chiefly upon the ulna. 



There was no epitrochleo -anconeus. 



Cebus variegPvtus. — Johns Hopkins Anat. No. 1. male, with a 

 humeral length of 78 mm. ; right side. 



M. biceps brachli., capita (onywvi et breve. — The two heads had 

 their usual origins, and the tendon of the longum was completely 

 within the shoulder capsule, although the bicipital groove was not 

 particularly deep. Muscle fibers developed at about the level of the 

 latissimus tendon. Fusion of the two heads took place at the distal 

 third of the brachium, and the common, tendinous insertion was 

 upon the radius. There was no trace of a lacertus fibrosus. 



M. coracobrachialis., partes profunda et med/ia. — The deep or short 

 part was large and well developed, with fleshy origin from the cora- 

 coid deep to the common tendon, and insertion upon the surgical 

 neck of the liumerus behind the latissimus tendon. In a second 

 specimen of Cebus {0. apella, Johns Hopkins Anat. No. 2) this part 

 of the coracobrachialis was absent. 



The coracobrachialis medius split from the conmion coracoid 

 tendon just below the latissimus and inserted upon the humerus, 

 beginning about 9 mm. below the latissimus and continuing for about 



