1899.] THE MYOLOGY OF THE EBENTATA. 331 



scapular head is noted as rising from just below the glenoid cavity 

 The fibres of the inner head have the same pulley-like arrangement 

 as in Myrmecopliaga, as shown by Cuvier and Laurillard's figure 

 (16), and by Kapp's description of them as forming a humeral 

 head for the flexor profundus digitorum (III.)' Of tlie five 

 specimens of Cydotlmrus of which we have records, three had only 

 one scapular head (17, IS, 21), whilst in two (19, 20) this was 

 double. In one of the first-named group (21) a continuation of 

 the muscle into the forearm, as in Tamandua and Myrmecophaga, 

 was present. In all the Myrmecophagidce the anconeus is large, 

 and especially so in Cydotlmrus. The Dasypodidce resemble the last 

 family in having, as a rule, two scapular heads, which may be called 

 anterior and posterior. The anterior rises fi'om the axillary border 

 below the glenoid cavity, and the posterior from the dorsum scapulae 

 in the region of the lower spine. This applies to Dasypus (22), 

 Tatusia (25), and Ohlamydophonis (27,28). In Galton's specimen 

 of Dasypus (23) the long head was apparently single, while in one 

 specimen of Chlamydophorus (27) there was a third scapular head 

 from the inferior margin of the bone. In the llanidce the scapular 

 head is also usually double, this condition having been noticed in 

 three cases (29, 31, 34) ; in two cases (32, 33) no division was 

 seen. In Orycteropus multiple scapular heads seem to be the rule. 

 In 36 there are three, viz. (a) glenoid, (b) from the posterior costa, 

 (c) from the angle, passing to the triceps and the latissimo- 

 olecranalis. In (35) only two were noticed, but oue of them seems 

 as if it would be more properly described as a scapular origin of 

 the latissimo-olecranalis, and the same thing seems to have been 

 present in (31). Macalister (VII.) notices that in a specimen which 

 he dissected the lower fibres of the inner head play round the 

 internal condyle and join the flexor profundus as in the Myrmeco- 

 phagidce. The anconeus presents no special features of interest 

 lu the Manidce and Orycteropodldce. In conclusion, we may point 

 out that all the Edentata, with the exception oE the Bradypodidce, 

 are remarkable for the great development and complexity of the 

 extensor cubiti and for the presence of additional scapular origins. 



EpitrocMeo-olecranalis. — We can confirm Galton and (rruber's 

 observations as to the constancy and remarkable development of 

 this muscle throughout the Edentata. 



Pronator radii teres rises from the internal condyle and seems 

 to be always inserted into the lower third or half of the radius. 

 Tbis arrangement we find to be so constant that it may be fairly 

 looked upon as an Edentate characteristic. 



Flexor mrpi radialis. — Unlike most mammals the Edentates 

 show some variability in the insertion of this muscle, though its 

 origin from the internal condyle is constant enough. In the 

 Bradypodidce it never seems to obtain its normal insertion into the 

 second metacarpal bone. In four specimens of Bradypus (2, 3, 

 5, 6) it was inserted into the rudimentary trapezium. Mackintosh 

 (5) found a small muscle, which he calls flexor carpi radialis 

 profundus, rising from the ulua and running down to the deep 



