The foot, like the hand, has two median digits which rest on the ground by their third phalanges; and an internal and an external digit, which are removed from it. The metatarsals are a little longer than the metacarpals. [Illustration: FIG. 51.--PELVIS OF THE OX: SUPERIOR SURFACE. 1, Iliac crest; 2, external iliac fossa; 3, sacrum; AA´, bi-iliac diameter; BB´, bi-ischiadic diameter.] =Unguligrades=: =Sheep=, =Ox= (Fig. 39, p. 61).--The pelvis of ruminants of this group closely resembles that of the horse, which we will study later on (see p. 99). That which we must at once point out is that, with regard to the ratio formed by a comparison of the bi-iliac and bi-ischiatic diameters, it may be placed between the ratio obtained in comparing those diameters in the pelvis of the carnivora and that of the solipeds. Indeed, in the ruminants, the distance which separates the ischia exceeds the width of one iliac only, and does not equal, as in the felide, the total width of the anterior part of the pelvis (Fig. 51). In the skeleton of the ox, which forms part of the anatomical museum of the École des Beaux-Arts, the bi-ischiadic diameter is 39 centimetres, whilst the width of one iliac crest is 29 centimetres, so that, in contrast to that which we find in the dog, the width of the ischiadic region is less than that formed in front by the addition of the iliac crests. The great trochanter is large, and extends beyond the level of the plane in which the head of the femur is found. In the ox, the linea aspera, instead of being a narrow crest, is spread out, and forms in reality a surface; the posterior surface of the femur. At the inferior and external part of this surface is situated a cavity which surmounts the corresponding condyle, and is known as the _supracondyloid fossa_. On the internal part of the same region there are a series of tubercles, which, because of their position in relation to the corresponding condyle, constitute the _supracondyloid crest_. The internal lip of the trochlea is much thicker and much more prominent than the external. The details which we have just now examined in connection with the ox are less marked in the sheep. The trochlea, narrow as a whole, is clearly separate from the condyles by a very marked constriction. The patella, which is thickened in the antero-posterior direction, has the shape of a triangular pyramid with the base upwards. Its posterior surface, which articulates with the trochlea, presents an arrangement which is adapted to the disposition of this latter--that is to say, the surface which is in contact with the internal lip is larger than that which articulates with the lip of the opposite side. The tibia of the ox is proportionately shorter than that of the sheep. The shaft of this bone is flattened from before backwards, in its inferior half. The median crest of the articular surface of the inferior extremity is the most prominent part of that region.