Chapman and Bischoff speak of a muscle common to all apes which starts from the tendinous attachment 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 anthropoids. 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 two portions of the pectoralis minor; it was connected for a space with the coraco-brachialis, and finally it was attached, in the upper part of the lower third of the humerus, to the inter-muscular septum which is found between the brachialis anticus and the triceps. In the chimpanzee, on the other hand, it has its origin in the _latissimus dorsi_, and divides into an anterior and posterior portion; the former is attached to the inner condyle of the humerus, while the latter is connected either with the middle or inner head of the triceps. In the orang the same division of this muscle may occur. In one of these animals I observed an anterior portion, very thin and semi-membranous, attached by an extremely slight tendon to the coracoid process of the shoulder-blade, while the hind portion issued from the _latissimus dorsi_. They were both in connection with the triceps and brachialis anticus. In other instances the muscle consisted only of the posterior portion, issuing from the _latissimus dorsi_. In the white-handed gibbon, the muscle issued from the region in which the tendons of the _latissimus dorsi_ and of the teres major are united, and was inserted into the fascia which is found between the bicipital and the brachialis anterior. This attachment may also occur in the centre of the shaft of the humerus. Chapman and Chudzinsky have observed anomalous instances of this formation in coloured races.[70]