164 ANTHROPOID APES. 



only imperfectly acquainted. It extends nearly as 

 far in the gibbon and orang, while in the chimpanzee 

 its attachment is higher up. Bisohoff observes, and 

 it was previously suggested by Vrolik, that in the 

 chimpanzee the coraco-brachialis muscle possesses 

 at its origin a moderately large second portion, 

 which tends downwards over the lesser tuberosity of 

 the humerus, and adheres to its edge. But I have 

 seen both portions of the muscle in question attached 

 to the coracoid process of the scapula in apes of 

 this species. In the gorilla, orang, and gibbon the 

 position of this muscle corresponds to that in man. 



Chapman and Bischoff speak of a muscle common 

 to all apes which starts from the tendinous attach- 

 ment of the latissimus dorsi on the edge of the lesser 

 tuberosity of the humerus, and tends downwards on 

 the inner side of the humerus, and to this muscle 

 they give the name latissimo-condyloideus. Bischoff 

 goes on to say that this muscle goes in some cases 

 into the fascia which covers the biceps; and in 

 others, as in the baboon, it is attached to the inner 

 inter-muscular septum and to the internal condyle 

 of the humerus. In the gibbon it only extends as 

 far as the centre of the humerus, but in the orang it 

 reaches to the condyle, where it is pierced by the 

 ulnar nerve. Bischoff adds that this formation is 

 wanting in man. 



This structure is indeed remarkable in anthro- 

 poids. The muscle starts in a lateral direction from 

 the insertion point of the latissimus dorsi. In the 

 gorilla alone I observed that it started from the 

 coracoid process of the scapula, together with the 



