1898.] MYOLOGY OP THE TERRESTRIAL CARKITORA. 159 



of Canis familiaris (45) out of six (see fig. 1). It was absent in 

 Canis aureus (50, 50 a), Cnnis mesomelas (51), Canis lagopus (53), 

 and Lycaon pictus (54). 



In the Ursidse Shepherd and Cuvier and Laurillard noticed it in 

 Ursus americanus (59, 62). Among the Procyonidse it was absent 

 in Procyon lotor (63, 64, 65) and Nasua narica (68), but was 

 found in Nasua fusca (69) and Cercoleptes (72) ; while among the 

 Mustelidae it was found in Galictis vittata (75), Galictis bnrhara 

 (76), Meles (85, 86), and Lutra (88, 93), but was not seen in 

 Ictonyx lihyca (84). Prom the foregoing we are of opinion that 

 the glutevis ventraHs may be distinguished from the entogluteus, 

 if carefully looked for, in most of the Carnivora. 



Gluteus profundus {Gluteus quintus, ilio-capsulans) . — This small 

 muscle is described very accurately by Douglas ^ in the Dog. It 

 rises from the ilium just above the acetabulum, and passes over 

 the capsule of the hip-joint to be inserted into the upper part of 

 the anterior surface of the shaft of the femur, between the origins 

 of the vastus internus and crureus. We have records of the 

 presence of the muscle in the following animals : — Felis pardus 

 (6), Felis pardalis (8), Cyncdurus (12), Geneita vulgaris (24), 

 Cynictis penicillata (31), Hycena striata (36), Canis familiaris (44, 

 45), Canis aureus (50), and Meles taxus (85). Owing to its small 

 size it is easily overlooked, and our notes do not enable us to say 

 whether it is constantly absent in any special genus or family. 



Pyriformis. — This muscle, as has already been mentioned, is 

 frequently so blended with the mesogluteus as to be with difficulty 

 made out. If the origin from the sacrum, however, be carefully 

 looked for, the muscle can usually be separated. It seems to be a 

 very constant muscle in the Carnivora, rising from the ventral 

 surface of the sacrum and being inserted into the top of the great 

 trochanter. Apart from its greater or less degree of distinctness, 

 we have met with no special variations. 



Obturator internus. — This has the human origin and insertion. 

 Where the tendon passes round the lesser sacro-sciatic notch its 

 deep surface is marked by five or six ridges separated by furrows. 



Gemelli. — In the Carnivora the two gemelli are seldom, if ever, 

 separate ; they form a continuous origin from the ventral edge of the 

 lesser sacro-sciatic notch, and He deep to the obturator internus, 

 overlapping it in front and behind. The anterior part, which 

 corresponds to the superior gemellus of human anatomy, is usually 

 the larger, though in one specimen of Lutra (88) only the pos- 

 terior gemellus ^^as present ; this, however, appears to have been 

 an individual variation. 



Obturator externus. — This rises from the outer surface of the 

 obturator membrane, but much more strongly from the bone on 

 the dorsal and posterior margins of the foramen. It is inserted 

 as usual into the digital fossa of the great trochanter. We have 

 met with no variations of it. 



' 'Descriptio Musculorum,' 1738, p. 14(i. 



