THE HOOFED MAMMALS. 161 



in point of size to Highland cattle, although its coat is still more shaggy. 

 The musk-ox is now restricted to Arctic America and the north of Green- 

 land, although in a past epoch it ranged over northern Asia and Europe 

 as far south as Britain. With the 

 sheep this ruminant agrees in its 

 hairy muzzle and the general struc- 

 ture of the molar teeth ; but the 

 horns are quite peculiar, those of the 

 adult males being greatly flattened 

 and expanded at their bases, where 

 they almost meet in the middle line 

 of the forehead, after which they bend 

 downwards by the sides of the face, 

 and then curve sharply upwards. 

 While they are whitish and fibrous at Fig. 90- MUSK-OX (Ovibos moschatus\ 



the base, at the tips they are smooth 



and black, with a nearly circular section. The small and pointed ears are almost 

 buried in the long hair ; the general colour is brown, and the short and sheep- 

 like tail is completely lost among the hair. In winter a woolly under-fur is 

 mingled with the long hair to form an efficient protection against the intense 

 cold of the regions inhabited by this animal. A peculiar feature of the feet 

 of the musk-ox is that the two hoofs of each are not symmetrical ; these being 

 partially covered with hair on the lower surface. In general habits musk- 

 oxen much resemble sheep, collecting in flocks of considerable size, among 

 which the proportion of old rams is comparatively small. The musky odour 

 from which the animal derives its name does not appear to be due to the 

 secretion of any special scent-gland. 



The last, or bovine section of the family, is represented by the buffaloes, 

 bison, and oxen, all of which may be included in the single genus Bos. All 

 are animals of very massive build, with a short neck, and the head carried 

 nearly in the line of the back, the largest members of the whole family being 

 included among them. From the sheep, the oxen, as the group may be 

 collectively termed, are markedly distinguished by the conformation of the 

 tall crowns of the molar teeth. In the upper jaw these have a nearly square 

 cross section, with a well-defined additional fifth column on the inner side, 

 and the whole of the valleys and clefts completely filled up with cement. 

 r \ he horns, which are massive, arid nearly as large in. the females as in the 

 males, are placed on the summit of the skull with their bases far apart, and 

 may be cylindrical or triangular in section, their -direction being at first more 

 or less outwards, after which they turn upwards at and near the tips. They 

 always lack the transverse knobs of the goats and the wrinkles of those of 

 the sheep, so that the surface is comparatively smooth, the colour being 

 dark. Internally the bony cores of the horns, like those of the goats and 

 sheep, are much honeycombed. In all cases the broad muzzle, in which the 

 nostrils are placed wide apart, is more or less completely naked and moist ; 

 there is no gland beneath the eye, and consequently no depression in this 

 region of the skull ; the bulls usually have an ample dewlap beneath the 

 throat, the long and tapering tail is generally tipped with a large bunch of 

 long hair, and there are no glands between the hoofs of either foot. The 

 udders of the cows are provided with four teats. As in the sheep and g-oats, 

 small lateral hoofs are retained. The majority of the oxen are confined 

 to the continents of Europe, Asia, and Africa, but one species of bison 

 12 



