Of the sea-dolphins we can only notice two. The first of these is the common dolphin, which is found in great numbers in almost all parts of the temperate and tropical seas. Apparently it is not often to be found on American coasts, but it has been captured in eastern harbors. It generally lives in herds, which will follow ships for hours together, leaping and gamboling on the surface of the sea, and yet keeping pace with the vessel without the least apparent effort. It feeds on fishes, to capture which, and hold them firmly, it has one hundred and ninety teeth, so arranged that when the mouth is closed the upper and lower ones fit in between one another like those of a steel trap and hold the prey in a grip from which there is no escape.
A full-grown dolphin is usually about seven feet long, but much larger specimens are occasionally found. The color is dark gray or glossy black above, and almost pure white on the lower parts of the body.
The bottle-nosed dolphin is a rather smaller animal, with a shorter and more pointed beak shaped rather like the neck of a bottle, and is purple black above and grayish white below. Its range is on the North Atlantic coast from Maine to Florida, on the Gulf coast, and also on some of the coasts of Europe.
Manatees and Dugongs
There is just one other family of water-mammals which it will be convenient to mention here, although they do not really belong to the whale tribe. These are the very curious creatures known as sirenians, the best known of them being the manatee and the dugong.
Of course you have heard of mermaids, those imaginary creatures of the sea, which were supposed in days of old to combine the head and body of a woman with the tail of a fish. Well, very likely stories of them were told in the first place by some traveler who had seen a manatee, for the animal has a queer way of raising its head and the upper part of its body almost upright out of the water and cuddling its little one in its flippers, so that from a little distance it really looks something like a human being with a child. But at close quarters the comparison would not be a very flattering one, for there is a kind of disk-like swelling at the end of the snout, and the skin is black and coarse and wrinkled like that of an elephant.
Manatees are found on the west coast of Africa, and also on the shores of South America, living near the mouths of the larger rivers. They never seem to leave the water of their own accord, and if by any chance they find themselves upon dry land, they are perfectly helpless, and can only roll over and over. One specimen seen in a zoo was quite a small animal, and had to be fed with milk out of a baby's bottle, while the keeper nursed it upon his knees. When it grew a little bigger it became very playful, and would tumble and roll about in its tank almost like a dolphin or a porpoise. And more than once it even succeeded in knocking its keeper into the water.
Another of these animals, caught at the mouth of the Essequibo River, lived in an aquarium for sixteen months. It was about eight feet long, and its tail was so powerful that every one was afraid the sides of its tank would be broken in by its tremendous blows. Its appetite was remarkably good, for it used to eat as much as eighty-four pounds of lettuces every day.
There is a species of manatee, also called sea-cow, formerly ranging the South Atlantic and Gulf coasts of the United States, but now seen only in the rivers and lagoons of southeastern Florida, where it has become so rare that the State prohibits its wanton destruction under penalty of a heavy fine.
The dugong is found on the east coast of Africa, and also on the coasts of Mauritius, Ceylon, the islands of the Indian Archipelago, and Western Australia. In many respects it is very much like the manatee. But it has a forked tail instead of a rounded one, and its body is bluish black above and whitish below. It lives in shallow water near the mouths of rivers, feeds on various water-plants, and is said to be so affectionate that if one of a pair is killed the other cannot be induced to leave the dead body, but will remain by it and allow itself to be slaughtered also.