a thin, wide, shovel-shaped tail, not set edgewise as in a fish, but across the body, so as to lie like a broad leaf in the water.

Who would think that a creature like this had anything in common with land animals? Yet so it is, for not only do we know that his ancestors had traces of hind legs, but his front limbs are quite as true arms and hands as those of any of the seals. Moreover, he has large broad grinding back teeth like the elephant, and in front he has small cutting teeth as a baby, though these are covered up by the gum as he grows older. In the Australian dugong, however, these teeth continue to grow and form good-sized tusks in the fathers.

What, then, is this curious animal? Simply a vegetable-feeder which has become fitted for a watery life—a gentle, peaceable animal, which keeps near the shore and grasps the seaweed with the sides of its upper lip, and then nips it off by a set of horny plates, which grow down from the roof of its mouth, and answer to the rough wrinkles on a cow’s palate. They may often be seen together, father, mother, and child, wandering up the river Congo in Africa, or the Amazons in South America, feeding entirely under water, and only raising their heads from time to time with a snort to take in fresh air. In olden times they probably thronged all the coasts on the sea-margin, for a hundred and fifty years ago there was another group of them, the Rhytinas, right up in the cold seas of Behring’s Straits, where the vast submarine forests of seaweed afforded them plenty of food. But the sailors found them such good eating, and the fatty blubber on their bodies was so valuable, that they were all killed twenty-five years after Behring first discovered them, and unless some care is taken, the more southern sea-cows may some day be exterminated in the same way.

* * * * *

And now that we have firmly grasped the fact that the seals and manatees, however altered in shape, belong to the four-footed and milk-giving group, perhaps we shall be prepared to understand how it is that the whales[186] are not fish, though this popular delusion is one of the most difficult to overcome. “Do you really mean then,” exclaim nearly all people who are not naturalists, “that a whale is not a huge fish?” Certainly I do! A whale is no more a fish than crocodiles, penguins, or seals, are fish although they too live chiefly in the water.

A whale is a warm-blooded, air-breathing, milk-giving animal. Its fins are hands with finger-bones, having a large number of joints (see Fig. 84); its tail is a piece of cartilage or gristle, and not a fish’s fin with bones and rays; it has teeth in its gums even if it never cuts them; and it gives suck to its little one just as much as a cow does to her calf (see Fig. 85). Nay! the whalebone whales have even the traces of hind legs entirely buried under the skin (see Fig. 84), and in the Greenland whale the hip-joint and knee-joint can be distinguished with some of their muscles, though the bones are quite hidden and useless.

Fig. 84.

Skeleton of a Whalebone Whale (Mysticete), and Section of the Mouth with Whalebone.

b, blowhole; a, upper arm; fa, fore arm; h, hand; p, th, l, small remains of pelvis or hip-bone, thigh, and leg; r, roof of the palate; w, w, plates of whalebone; f, whalebone fringe.

We see then that the whale undoubtedly belongs to the same type as the four-footed land animals, although it branched off into the water so long ago that it

Footnote 186. Cetacea—cete, a whale.

may have come from some very early milk-giver. But why then has it become so like a fish? For the same reason that the penguin’s wings have become so fin-like, and the seal’s arms and legs have become flippers, namely, that during the long time in which the whales have taken to a watery life, those which could swim best and float best in the water have been the most successful in the struggle for existence; and as a fish’s shape is by far the best for this

purpose the warm-blooded milk-giver has gradually imitated it, though belonging to quite a different order of animals.

Fig. 85.

The Humpback Whale[187] suckling her young (after Scammon).

We saw this imitation already beginning in the seals, with their bodies sloping off towards the tail and their legs fastened back in a line with the body; but they have not gone so far in this direction as the whales have, since they still have hind legs and furry bodies. The sea cows, on their line, have gone a little farther, for they have lost their hind legs, and their skin is smooth, with very few hairs upon it. But it remained for the whales to take up the best fish-form, the old spindle-shape, thinning before and behind, with the strong fleshy tail ending in two tail lobes, which act like a screw in driving the body along.

Footnote 187. Megaptera.

Any good drawing of a whale shows at once how admirably these animals are fitted for gliding through the water (see Fig. 85). True, many of them have enormous heads, but these always have long face-bones ending in a rounded point, and even the huge head of the sperm whale (see Fig. 87), eighteen feet long, six feet high, and six feet wide, is rounded off above, and gradually thins away below, like the cutwater of a ship. The eyes are very tiny and so little exposed, that it is difficult to find them; there are no outer ears, though the bones within are large and probably very useful for hearing in water; the bones of the neck are seven, as is the rule among milk-givers, but they are so flattened and firmly soldered together, and so covered with blubber, that there is not even a hollow between the head and the body; while to crown all, the skin is perfectly smooth so as to offer no resistance to the water. Here, however, would be a disadvantage in the loss of the furry covering, since most of the whales travel into cold seas, were it not compensated by the great mass of oily fat or blubber which fills the cells in the under part of the skin, and keeps the whole body warm; and thus the whale, by a covering of fat often as much as a foot and a half thick, solves the problem of a warm-blooded animal, with a smooth gliding body, living in icy water without having its blood chilled.

In every essential for swimming, then, whales are as well provided as any fish, while their immensely strong backbone, and the long cords or tendons running from the mass of muscle on the body to the tail, give them such tremendous power that a large whale makes nothing of tossing a whole boat’s crew into the air and breaking the boat in two. But, though they are so far true water-animals, yet they cannot live entirely below as fish can, for they have no apparatus for water-breathing. The outside of their body takes on the appearance of a fish, but inside they have the true lungs, the four-chambered heart, and all the complicated machinery of a warm-blooded animal. Therefore, though a whale may dive deep and remain below to seek its food, yet before an hour has passed even the largest of them must come floating up to the top again, to blow out the bad air through the nostrils at the top of the head, and fill the capacious lungs with a fresh supply. It is then that, partly because of the water which has run into the blowhole, and partly because the rush of breath throws up spray from the sea, we see those magnificent spouts of water which tell that a whale is below. The older naturalists thought that these spouts were caused by the water which the whale had taken into its mouth; but this is not so, and Scoresby, the great Arctic traveller, states distinctly that if the blowhole of the whale is out of the water only moist vapour rises with the breath, while when it makes a large spout this comes from its blowing under water and so throwing up a jet.

If, however, the whale is a simple air-breather and yet swims under water with its mouth open, how comes it that this water does not run down the windpipe and choke the lungs? This is prevented by a most ingenious contrivance. At the top of our own windpipe there is a small elastic lid which shuts when we swallow, and prevents water and food from running down to the lungs. Now, in the whale the gristle answering to this lid runs up as a long tube past the roof of the mouth into the lower portion of the nose, and is kept there tightly, being surrounded by the muscles of the soft palate. The upper portion of the nose cavity then opens on the forehead by means of one or two “blowholes,” as the outside nose holes are called; so that when the blowholes are closed the whale can swim with its mouth open and feed under water, and yet not a drop will enter its lungs.

A large sperm whale will often remain twelve minutes or more at the top of the water, taking in air at the single blowhole in the front of its head, and purifying its blood, and then with a roll and a tumble it will plunge down again, and remain for an hour below, trusting to a large network of blood-vessels lying between the lungs and the ribs to supply purified blood to its body and retain the impure blood till it comes up again to breathe.

But the smaller whales and porpoises, which play about our coasts, have to come up much more often, and even when they are not tumbling and jumping, as they love to do, you may see them rising at regular intervals as they swim along, their black backs appearing like little hillocks in the water, as they “blow” strongly from their single nose-slit, take a quick breath in, and sink again to rise a few paces farther on and repeat the process.

Thus provided both with swimming and breathing apparatus, these purely air-breathing animals wander over the wide ocean and live the lives of fish, making such good use of food which cannot be reached by land animals, or those which must keep near the shore, that we shall not be surprised to find that the whale family is a very large one.

But it is curious that the fierce animals of prey among them should be, not the huge whales but the smaller Dolphins, Porpoises, and Grampuses; and this shows how different water-feeding is to land-feeding, since, because the water is full of myriads of small and soft creatures, the sperm whale feeding on jelly-fish, and the large whalebone whale feeding on soft cuttle-fish and the minutest beings in the sea, are those which attain the largest size.

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