328 MESSES. B. C. A. AVINDLE AND F. G. TARSONS ON [Mar, 7, 



below the lesser tuberosity of the humerus is specially marked ofE 

 from the rest of the muscle. The name of subscapulo-humeral, 

 which sufficiently indicates its nature, has been suggested for this 

 slip (1, 2, 5, 10). In one specimen of Bnidijims (2) the sub- 

 scapularis was divided into three parts, the hindmost of which was 

 the subscapulo-humeralis. In Myrmecoijhaga Macailister(l.) found 

 the muscle intersected by ten tendinous planes, and the specimen 

 now in the E.C.S. Museum (11) shows the same condition. 

 We further found in this specimen that five separate nerves, all 

 from the dorsal part of the brachial plexus, entered the muscle. 

 Macalister states that there are two accessory slips to the muscle 

 in this animal : (a) the subscapulo-humeralis, and (6) " a triangular 

 slip from the fossa above the subscapular nerve." Poiichet (II.) 

 found that the tendon of insertion split into upper and lower 

 parts and between them was the short head of the biceps ; it is, 

 however, just possible that he may have mistaken the upper edge 

 of the supraspinatus, which is very prominent in this animal, for 

 part of the insertion of the subscapularis. In Tamandua (14) the 

 muscle is also considei'ably broken up. In no other Edentate was 

 any special feature of interest noted in connection with this 

 muscle. 



Coraco-brachialis. — An Edentate characteristic of considerable 

 interest is the great frequency of occurrence of the coraco- 

 brachialis longus throughout the Order. In the Bradi/podidce, 

 Bradypus and Cholcepus, as is so often the ca'e, differ in their 

 myology. In the former the coraco-brachialis medius alone is 

 present (1, 2, 3, 4, 5, 6), and in our own specimen (1) we were 

 careful to notice that the musculo-cutaneous nerve passed above 

 the muscle, i. e. between it and the bone. In Choloejvis (8, 10) the 

 brevis and longus alone were present, though Galton (X.)in another 

 specimen says that he found only a thin cord-like middle variety. 

 In the MyrmecophagidcE, Myrmecophaga (11, 12) and Tamandua 

 (14, 15, 16) have the longus only attached to the supracondylar 

 arch, and given off from the short head of the biceps about the 

 middle of the arm ; whilst in the four specimens of Gyclothurus of 

 which we have records (17, 18, 20, 21) no coraco-brachialis at all 

 was present. In iheDusypodidce the longus and brevis were present 

 in two specimens of Dasypns (22, 23), but in another specimen 

 described by Wood (Journ. of Anat. & Phys. i. p. 51), and in 

 Cuvier and Laurillard's specimen (25), the longus only was found. 

 In Tatusia the longus and brevis were present in one specimen 

 (25), the longus only in another (26). In Chlamydophorus the 

 muscle was totally absent in Hyrtl's specimen (28), whilst in 

 Macalister's (27) the brevis was present. In the Manidce the 

 muscle was totally absent in five specimens (29, 30, 31, 32, 34), 

 but in one (33) the longus occurred. In Orycteropus (35, 36, 37) 

 the longus alone is present. From the above it will be seen that this 

 muscle is very variable in its condition throughout the Order, not 

 alone varying in different genera but in different specimens of the 

 same animal. 



