We need not look far to see these three chief characters of the vegetable-feeders in active work. Look at any horse as he grazes in the meadow, and see how his under jaw works from side to side as soon as he has a good mouthful. A peep into his mouth will show that he is using broad flat back teeth to grind the grass to pulp (see Fig. 67), and he will go on eating all day without overfilling the large stomach which lies within his barrel-shaped body. And as to his defences, if he is vicious, he will soon show that his front teeth are good weapons, while his hoofs will deal an ugly blow.

Then turn to the cow, quietly chewing the cud by his side; you will find that she has no upper front teeth, but only a hardened gum, upon which her under teeth bite as she crops the grass; but she too has broad flat teeth behind, while within she has a stomach with four compartments, and when she has filled one of these full of half-chewed grass, she lies down, and with a slight hiccough returns a ball of food to her mouth to be leisurely ground down. It is not difficult to see that to animals, such as wild cattle, antelopes, goats, and sheep, which often have to go far to seek their food, an arrangement of this kind, by which they may store provender in a larder for quiet enjoyment by-and-by, must be a great advantage. But the cow cannot defend herself with her teeth since she has no upper ones in front; in their stead she has strong horns which are quite as dangerous, so that an angry bull is an enemy not pleasant to meet.

Lastly, there is another fierce vegetable-feeding animal almost as dangerous as a bull, though we no longer come across him in England; for the Wild Boar, as he still flourishes in the forests of Germany, can inflict very ugly wounds with his lower eye-teeth which grow out and project over his upper lip, forming large tusks.

So we see that while the vegetable-feeding animals have three characters in common, namely, large flat grinders, a capacious stomach, and defensive weapons, their defences, on the other hand, may be of three different kinds, and they may depend upon horns, hoofs, or teeth for protection.

Now in the beginning, when we first meet with the milk-givers, these defences were not so complete in any of the vegetable-feeders as they are now. Of the elephants alone it may perhaps be said that they had large and formidable ancestors.[159] As to the rest, the huge hippopotamus and sharp-tusked boar were only represented by small animals;[160] and even later, when the hogs branched off in a line of their own, they had at first only ordinary teeth, which did not grow out as tusks.

Footnote 159. The Dinocerata of the Middle Eocene of America. These gigantic extinct animals, with tusks and horns, but very small brains, are believed by Professor Marsh to have connected the two groups the elephants and the hoofed animals among the early milk-givers.

Footnote 160. Anoplotherium; for this form and others, see p. 256.

So, too, the fierce horned rhinoceros had as an ancestor a hornless tapir-like creature,[161] and the graceful hoofed horse a little creature no larger than a fox, with five separate toes on his feet.[162] Lastly, all the horned animals which chew the cud,—oxen, buffaloes, antelopes, and deer,—were nowhere to be seen, and in their place were only some small elegant creatures without horns.[163]

It is only at a later period when the flesh-feeding animals grew strong and dangerous, and the vegetable-feeders had to struggle for their lives, that we begin to find the remains of hogs and hippopotamuses with tusks, rhinoceroses with nose-bones, and fleet horses which could take to their heels, or bite and kick their enemy to death; of stags with antlers, ever increasing in size; and of bulls and buffaloes, goats and antelopes, with true horns. For not only by this time were they persecuted by the flesh-feeders, but they themselves were becoming very numerous, and it was the strongest only that could secure feeding-grounds or carry off wives.

* * * * *

It is very curious to see the different ways in which the three chief lines of vegetable-feeders secured these advantages to themselves. First, there were the hogs and hippopotamuses. The hogs did not grow to any enormous size, but their thick skins were a great protection to them, and their eye-teeth became their defence, growing out from the lower, and sometimes from both jaws into huge tusks; while their broad, round, flexible snouts served them to turn up the ground, and so get at roots and underground

Footnote 161. Paleotherium.

Footnote 162. Eohippus.

Footnote 163. Xiphodon.

fruits such as other grass-feeding animals could not find; though at the same time they did not despise snakes or toads, and have become omnivorous animals. And so they have spread nearly all over the world; in Europe and Asia as wild hogs, and their wives the sows; one peculiar form, the Babirusa, being found only in Celebes; in Africa as

large Wart-hogs, some as big as donkeys, with two pair of strong tusks curling out of the mouth; while in South America the family is represented by the small Peccaries, which travel about in herds, and have no tusks to show; but which, nevertheless, are bold and fearless, for they have within their lips short lancet-shaped tusks, which inflict fearful wounds. Only in North America, north of Texas, no wild creature of the hog family now lives, though in ancient times there were plenty of them.

Fig. 67.

The Babirusa; the double-tusked hog of Celebes.

Meanwhile the warmth-loving hippopotamuses, the hog’s nearest relations, with huge grinding teeth behind, sharp front teeth, and tusks within their lips, took to a water-life in the Old World.[164] When we look at their immensely powerful bodies, and their short stout legs with four strong hoof-covered toes, and learn how rapidly they can gallop on land, and how furiously they charge an enemy in the water, snapping their great jaws which will kill a large animal at one crunch, we do not wonder that they can hold their own, especially as they always live in herds. Yet large and powerful as they are, they have not spread far over the earth, for though in past ages the hippopotamus swam in the river Thames, and grazed and left his bones in the ground upon which London streets now stand, yet after a time they crept down to warm Africa, where they may now be seen lazily basking on the surface of the Nile or of the river Zambesi by day, and making tracks by night into the swamps and jungle to feed on the coarse rank grass. They are well fitted for their life, for their thick naked skin, with pores which

Footnote 164. See picture heading.

give out a fatty oil, keeps them from chill in the water; their eyes are set well back on their heads, so that as they float deep they can still look around, and the slits of their nose, and the openings of their ears, can both be closed and made water-tight when they dive, while their slow breathing enables them to remain a long while under water.

The second line was that of the rhinoceroses, tapirs, and horses, or the uneven-toed animals which have one or three toes on the hind feet. They took to very different means of defence. The Tapirs,[165] large, heavy, and with enormously tough hides, seem to depend chiefly upon their great strength for defence. Starting in warm times in the Old World, they have wandered in their day nearly all over the globe, dying out in later times, till now one kind is left solitary in Sumatra and Malacca, and the remainder have found their way down to South America, where they tear the branches from the trees with their short movable snouts, and feed peaceably at night unless attacked, when they make a furious rush at their enemy and conquer by sheer force.

The rhinoceros, the tapir’s nearest relation, is even better defended; his skin is so thick and hard that in the Indian rhinoceros it actually forms a kind of jointed armour; his skull is wonderfully strong, and his nose is supported by thick bones, on the top of which are one or two solid horns, which are formed by a modification of the hairs of the skin growing matted together.[165]

And now notice, just as we saw that the horned

Footnote 165. See picture heading.

cow has no front upper teeth, so too the rhinoceros, though his horn is of quite a different kind, has in some cases lost his front teeth, which he does not need, since he rushes with his horn at his enemy instead of biting. Like the hippopotamus, the rhinoceros once wandered all over Europe and Asia, and when the great cold came on, the woolly species which roamed far north was often caught in the frost and snow of Northern Asia, where his fleshy body has been found preserved in the ice. Now he too has taken refuge in the warm parts of Asia and Africa, where he either grazes on the plains or plucks the leaves from the trees in the jungle with the fleshy flap of his upper lip.

Fig. 68.

Skeleton of a Wild Ass.

i, incisor teeth; g, grinding-teeth, with the gap between the two sets as in all large grass-feeders; k, knee; h, heel; f, foot; t, middle toe of three joints carrying the hoof; s, splint, or remains of one of the two lost toes; e, elbow; w, wrist; h, hand-bone; 1, 2, 3, joints of the middle toe.

But of all the animals of this three-toed group the Horse has the most interesting history, because we can read it most perfectly. The only certainly original wild animals of the horse tribe now living are the Zebras, Quaggas, and Asses of Asia and Africa; yet strange to say, it was in America that this tribe began, for there we find that tiny pony[166] not bigger than a fox, with four horn-covered toes to his front feet (and traces of a fifth) and three toes on his hind ones. Then, as ages went on, we meet with forms, still in America, first with four toes on the front foot, and then with only three toes on all the feet, and a splint in place of the fourth on the front ones. In the next period they have travelled into Europe, and there, as well as in America, we find larger animals with only three toes of about equal size. One more step, and we find the middle toe large and long, and covered with a strong hoof,

Footnote 166. See p. 213, and picture heading, p. 209.

while the two small ones are lifted off the ground. Lastly, in the next forms the two side toes became mere splints; and soon after, in America and in Europe, well-built animals with true horse’s hoofs abounded, the one large hoof covering the strong and broad middle toe. For what we call a horse’s knee is really his wrist, and just below it we can still find under the skin, those two small splints (sw) running down the bone of the hand, while the long middle finger or toe, with its three joints (1, 2, 3), forms what we call the foot. It is by these small splints

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