412 THE OSTEOLOGY OF VULPES MACROTIS. 



ing of the carnivora as a group, Flower says in the work just cited, that " the pelvis 

 is generally elongated and narrow, the ilium and ischium being in a straight line, 

 and of nearly equal length. In most species the ilia are straight, flattened, and not 

 everted above [makes reference to his figure of the pelvis of a dog, Fig. 115, p. 

 317], the iliac surface is very narrow and confined to the lower part of the bone, 

 as the acetabular and pubic borders meet in front above ; the gluteal surface looks 

 directly outwards and is concave ; the sacral surface forms a broad flat plane above 

 the attachment to the sacrum, the crest being formed by the united edges of the 

 sacral and gluteal surfaces, instead of the iliac and gluteal surfaces, as in man. 

 The symphisis is long ; it includes part of both pubis and ischium, and commonly 

 becomes completely osseous in adult animals. The thyroid foramen is oval, with 

 its long axis parallel to that of the whole bone. The ischia are wide and divergent 

 posteriorly. 



" In the Hyaena the pelvis is shorter and wider than in most other carnivora, 

 both the upper ends of the ilia and lower ends of the ischia being considerably 

 everted." 



Now in Vulpes macrotis the pelvis is by no means unlike that part of the 

 skeleton as we find it in some of the more fox-like species of the domesticated dogs. 

 Flower figures the "ventral surface of right innominate bone of dog (^)" in his 

 Osteology of the Mammalia and in its general features it very closely resembles 

 the same surface of the pelvis of the fox now being considered, and the description 

 above quoted likewise answers very well in describing the same. There are plenty 

 of half-breed Indian dogs in the Indian camps of the northwestern parts of the 

 United States that doubtless possess pelves with characters almost identical with 

 those of Vulpes. 



The ilia of this pelvis have the sacrum of the vertebral column wedged in 

 between them quite as firmly as we find it in man and many other animals, and 

 the articular surface for the articulation with the sacrum is of the same roughened 

 character. Above this surface the blade of an ilium rises for more than a centi- 

 metre, its superior crest being convex, while its external surface is markedly con- 

 caved. The posterior borders of the ilia are very nearly in the same plane with 

 the ischia, and in fact the pelvis as a whole is much compressed in the antero- 

 posterior direction. Scarcely any indication of a "greater sacro-sciatic notch" or a 

 " lesser sacro-sciatic notch" is present, though on the anterior rim of the basin of 

 this pelvis, a rudimentary anterior superior spine is seen, the anterior inferor spine 

 being well-marked and conspicuously developed. Either acetabulum is a hemis- 

 pherical concavity with an average width of nine millimetres. Its base is not 

 perforated by a foramen, while the cotyloid notch at its lower part is distinctly 

 marked. The symphysis pubis is very firmly co-ossified for its entire length, the 

 suture being almost obliterated upon its dorsal aspect. It has a length of 2.3 cms. 

 and the pubic arch is wide and much concaved. Each obturator foramen is very 

 large and of a subcircular outline, with an average diameter of eleven millimetres. 

 In the middle line at the narrowest place their peripheries are but 3.5 millimetres 



