We see, then, that it is quite possible for land-animals to have near relations specially adapted for a sea life. But the otter is still distinctly a four-footed creature, with free arms and legs, and we can trace his connection with the weasel tribe. It is quite different with the three groups of real fin-footed animals--the Seals and Walruses, the Manatees, and the Whales. Though we can trace their likeness bone by bone to the land animals, yet they have become so different as to show that they must have branched off long long ago; so long indeed that we cannot even guess at the relations of the whales, while the seals have only a distant resemblance to the bear family, and the sea-cows or manatees to the ancestors of the hoofed animals and elephants. Nor shall we wonder to find the whales so much the most fitted for the sea, when we learn that they were already living in the water when we first meet with the great army of milk-givers (see p. 211) just after the Chalk Period, so that they have probably had a much longer spell of watery life than the seals and sea-cows, whose remains we only find later. Yet even the seals are so much altered from anything we see on land, that few people would believe at first sight that they have the same skeleton as a bear. We need not leave the British shores to study these pretty creatures, for they still come to the coasts of Wales, Cornwall, and Ireland; while in the Hebrides they may be seen lying fast asleep on the rocks at low tide out at sea, one, placed higher than the rest, keeping awake as sentinel to give warning at the least approach of danger. But if we begin our study with the common seal we shall be much puzzled, for he is very unlike a land animal. His round neckless body tapering away to the tail, where the hind flippers stretch out behind like fish’s fins, reminds us far more of a tunny fish than of a four-footed milk-giver; while the front flippers, coming out so finlike from his side, give us very little idea of legs (see Fig. 81). No! in order to compare these fin-footed[181] creatures with land animals we shall do far better to travel up to the Aleutian Islands at the entrance of Behring’s Straits, and visit the Fur Seals and Sea Lions, from which we get our seal-skins, and the Walruses which sometimes lie there sleeping on the rocks, though their real home is farther north within the Arctic Circle, round the coasts of Nova Zembla, Spitzbergen, and Greenland. [Illustration: Fig. 80. Skeleton of a Sea Lion. Showing how the whole foot rests on the ground, as in the Bear Family. _th_, thigh; _l_, leg; _h_, heel; _f_, foot; _a_, upper-arm; _fa_, fore arm; _ha_, hand. ]