Footnote 180. Enhydra marina.

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

Footnote 181. Pinnipedia.

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.

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.

These creatures, although they have “flippers,” and are truly fin-footed, are much more like land animals than the smaller seals, for they plant their whole foot on the ground as a bear does, and walk, or, more properly, “flop along” on all fours. A mere glance at the skeleton of the sea lion, which is one of these higher kind of seals with a slight outer

ear,[182] shows that it is a four-footed animal, with five toes to each foot, the great toes and the thumbs being the largest. We can see distinctly the short thighs and the long shanks, which give the hind flippers their lanky appearance, and we see, too, the broad stumpy arms, which give such strength to the front flippers in swimming. For the eared seals and walruses use their fore flippers very much in the water, while the true seals swim almost entirely with the hind flippers, and use the front ones chiefly for guiding themselves.

And now if we turn to the living fur seal we find that the reasons are twofold which make us forget that his limbs are legs. In the first place, the skin of his body comes down very low over his arms (see Fig. 81), while the hand is encased in skin, with only mere traces of nails upon it Then as regards his hind legs, not only are the feet made into flippers, in which the toes are joined by a loose flexible skin, so that they can move them freely when swimming, but the legs themselves are strapped back by a skin passing right across his tail, so that his thighs are kept flat against his side, and only the lower part of the legs has power to move. We lose sight, then, of the limbs, and see very little more than the feet, which are disguised by being turned into flippers.

Now if we once think what is the object of a seal’s life, this curious change in its body is at once explained. For seals are the hunters of the sea; fish-food is to them what flesh-food is to lions, wolves, and bears, only that they have a much wider field to hunt in, for they have the whole ocean

Footnote 182. Otariidæ (ous, otos, an ear), eared Seals.

for their feeding ground, and no one to dispute it with them but the sea-otter in places near the land, and the porpoises and other fish-feeding whales out at sea. In consequence of this we find seals of some kind in almost all parts of the world, except the Indian Ocean, though they evidently prefer the cooler regions. Even the large sea lions live in the North Pacific, as far up as the Aleutian Isles, and in the South Pacific down to the Falkland Islands and Kerguelen’s Land, and play about the shores of the Cape, New Zealand, and Australia.

Fig. 81.

A Fur Seal,[183] one of the Sea Lions; and a common Seal.[184]

Showing how the Sea Lion walks on the flat hind feet, while the seal’s flippers lie back in a line with the body; note also the absence of an external ear in the seal.

They have evidently been very successful in exchanging flesh-feeding for fish-feeding, and if we consider for a moment what changes a four-footed land animal would wish to make in its body in order

Footnote 183. Callorhinus (Otaria) ursinus.

Footnote 184. Phoca vitulina.

to swim and dive in the water, we shall see that these changes have taken place in the seals.

First, a flexible body is required to wind and twist rapidly in the water, and this the seal arrives at by having the cushions of gristle between its joints very large and thick, while even its ribs are joined to its back by gristly rods, making its whole body very lissom. Next, a small head, offering little resistance to the water is an advantage, and this we find in all seals, while the short neck and extremely sloping narrow shoulders well encased in fat, make the body slope away gently with no jutting angles, but a round smooth surface from head to tail where it narrows like the tail of a fish. The next step is to do away with long angular arms and legs, which would impede it in diving and swimming, and here the seal meets the difficulty, not by losing its leg and arm bones, but by having them so shortened and encased in the skin that only the useful broad flippers are free, while the hind legs are set upon a very narrow hip joint (see Fig. 80), so that they bend backwards and work close to the body. Lastly, such a warm-blooded animal would want clothing to prevent it from being chilled in icy cold water, and here we find two protections. First, under the skin is a layer of oily fat, which, while it reminds us of the fat accumulated by bears before they settle down to their winter’s sleep, has become in the seals a dense oily mass, acting like a thick blanket in keeping up the warmth of the body; and secondly, the seal, like its distant relations the bears, has a dense furry covering, and over this a number of coarse long hairs, which give it that shining oily look we notice in all seals. No doubt every one has wondered, when watching seals in zoological gardens, where the fur can be which makes our sealskin muffs and jackets. The fact is, that this under fur is quite out of sight in the living seal, being covered by the coarse hairs; but if we could turn these aside, even in common seals, we should see the soft undergrowth beneath, and in the fur seals it is much thicker. Now the roots of these coarse hairs are deeper in the flesh than the roots of the soft undergrowth, and when the uppermost layer of the skin on which the fur grows is sliced off, the coarse hairs are cut away from their deep roots below, and can then be pulled out, leaving only the fur behind.

The seals then, while they are in all main points constructed like land animals, have gained many advantages, not by having new parts, but by the old ones becoming so modified as to make them admirably fitted for a watery life; and when we add that they have large eyes well adapted for seeing under water, keen ears with little or no outer ear, which would be useless, but a very acute hearing apparatus within, and nostrils which will close firmly and keep the air in and the water out when they dive, we must acknowledge that they make good use of all parts of their body. Indeed, their breathing apparatus is the most curious of all, for they can remain under water sometimes for twenty minutes, and meanwhile the circulation of their blood is probably controlled by large reservoirs in the veins, which prevent it going back to the heart and lungs till it can be purified by fresh breath.

Now, if all these changes from a land to a water-frequenting animal have been made gradually, we shall expect to find some forms less altered than others, and so it is. The Walrus, which is not a seal, but a creature with a thick hide having no fur and only a few scattered hairs upon it, and long tusks in his mouth, is much more of a land-animal than the seals. He passes a great part of his life sauntering along on the low shores of the Arctic seas, digging up mussels, cockles, and clams with his long canine teeth or tusks; and in accordance with this we find that his hind legs are much freer than even those of the sea-lions, for the skin binding them to his body is broader and his hips are stronger, so that, as he throws his front flippers forwards, he can also throw out his feet and walk on all fours in a strange straddling manner. He is remarkably fierce and strong, and Captain Scoresby caught one once in the act of killing and eating a large narwhal, so that they are evidently not afraid of attacking even large animals. The walrus is even said to stand at bay on shore and fight his great destroyer the polar bear, throwing up his head so as to strike forcibly with his sharp tusks, but in this battle he is generally defeated. His tusks alone would suggest that he lives a good deal on land exposed to dangers, for his more aquatic relations the seals are without tusks, and though their teeth are sharp enough, and they fight among themselves, yet their way of escaping the great tyrant of the ice-fields is to slip into the water.

Beyond his tusks, and the fact that by sleeping many weeks on the ice in autumn he reminds us of the bears, the walrus’s life is not very interesting. They live in large shoals in the Arctic sea, climbing the rocks and ice with the help of their tusks, which they drive into the crevices and so haul themselves up. During the colder times just before our own, they came down into much lower latitudes than now, and we find their bones as far south as England in Europe and Virginia in America, and even in our day one has been seen off the west coast of Skye; but we know very little of their daily life or how they bring up their young ones.

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