1880.] NATURAL SCIENCES OF PHILADELPHIA. 163 



fundus, and in the presence of the additional extensor tendons it 

 differed. 



As might be expected from the elongated form of the pelvis and 

 the absence of the round ligament of the hip-joint in the Orang, the 

 glutei muscles differ somewhat from those of man. The glutseus 

 magnus (PI. 12, e) in the Orang — not as large or as fleshy as its glu- 

 teus medius — is inserted together with the tensor vaginae femoris, 

 which is scantily developed, if at all, into the fascia lata of the thigh, 

 the glutieus medius being inserted into the great trochanter. Parallel 

 with the lower edge of the glutteus medius (PI. 12, c), is seen a small 

 muscle rising from the edge of the great sciatic notch, and inserted 

 into the great trochanter (PI. 12, b). This muscle seems to corres- 

 pond to part of the pyriformis in man, the sacral portion of the 

 muscle not being developed in the Orang. The glutseus minimus 

 is represented by a muscle arising from the external edge of the 

 ileum, and passing almost verticall}^ downwards until inserted into 

 the great trochanter, close to the pyriformis (PI. 12, a). At first 

 sight this muscle seems much displaced if it is the gluteus mini- 

 mus, but if one can imagine the ileum (PI. 12, d) in the Orang to 

 be widened outwardly to the same extent as seen in man, there 

 would be little or nothing anomalous about the muscle. From 

 the position of the glutwus minimus in the Orang, it would seem 

 that this muscle would supplement, to a certain extent, the want 

 of the ligamentum teres, which, it Avill be remembered, is absent 

 in this ape. 



In the Chimpanzee there is so little that is peculiar about the 

 gluteus minimus that I had no difficulty in identifying it, and the 

 same can be said of the Gorilla. In the account of the Chimpan- 

 zee by TrailP however, the glutreus minimus is described as a 

 distinct new muscle, the scansorius ; the muscle I have described 

 as pyriformis, Traill regarded as the glutanis minimus, the pyri- 

 formis, according to Traill, being absent. Since then, this so- 

 called scansorius muscle has been referred to b}^ Bischoff", Owen, 

 Huxley and others, as a distinct muscle. With all deference to 

 such eminent anatomists, I cannot see any essential difference 

 betAveen the scansorius of Traill, and the glutaeus minimus in man.^ 



1 Wernerian Transactions, p. 18, 1821. 



^ On looking up the literature upon the anatomy of the Orang, I find 

 t'liat in 1876 Prof: Baruard, o]). cit., considered the scansorius as being 

 homologous with the glutaius minimus, and mentioned in his paper that 



