30 THE OX AND ITS KINDRED 
are totally wanting on the face, limbs, feet, and groin 
of all kinds of cattle, as they are also in certain of the 
larger antelopes, such as eland. Moreover, the feet 
of cattle are cleft only for a very short distance above 
the hoofs — a feature which is probably due to the 
need in such beasts for a firmer type of foot than that 
suitable to animals living on softer ground, where 
lateral expansion of the hoofs is an advantage. 
As regards the total absence of all specialised 
skin-glands in cattle, Mr. R. 1. Pocock^ has suggested 
that " large ruminants are much more easily kept in 
view by members of their own tribe than small ; or if 
they live in thick bush, are more easily followed by 
hearing, as they crash away in a state of panic 
through the vegetation." Accordingly they do not 
need a strong scent to be left on the track along 
which they have to pass ; or, at all events, they have 
to do without the glands for this purpose. 
In addition to this total absence of specialised 
skin-glands, cattle are characterised by the presence 
of four teats to the udders of the females. 
In the domesticated ox the coat is short and 
sleek, but that of the bison is much longer and 
rougher in winter, and the Tibetan yak has a mass 
of long hair fringing the flanks and the tail likewise 
clothed with hair of a similar type. 
There is a slight variation in regard to the number 
of the ribs in the different species of cattle. In the 
ox itself the number of neck, or cervical, vertebrae 
is seven, as in very nearly all mammals ; these are 
followed by thirteen rib-bearing, or dorsal, vertebrae, 
and these again by the six ribless, or lumbar, vertebras 
of the loins. Then come the five united vertebrae 
^ Proc, ZooL Soc. London^ 1910, P» 983. 
