But this expression has been altered from its true meaning, and what are now called Amphibia, are the animals like the Seals, etc., which are organized for living in the water, but which can, with difficulty move about on the land. Very curious animals are found in the Seal family. Their bodies are long and cylinder-shaped, with many of the characteristics of the Fishes; and their limbs are converted into fins by being provided with broad connecting webs. The fur of these various animals is composed of a woolly compact coat, the thickness and fineness of which increases with the severity of the climate they inhabit; and which is covered by rather coarse hairs lubricated with oil, the object of which is to prevent the water from penetrating to the skin. A thick layer of fat protects the body against cold, especially in the species which inhabit the frigid regions. The Seal family live in numerous troops, and feed on Fishes, Mollusks, Crustaceans, etc. They are famous divers, and although they must come to the surface to breathe, they can remain a long time under water. This is explained by a peculiarity in their circulation. They are provided with reservoirs in which the blood accumulates while the lungs are inactive; and the animal is not suffocated while under water, because suffocation only comes from the stoppage of circulation as soon as the breathing is suspended, and in this case the circulation continues all the time the animal is under water; and it is only when the blood overruns these reservoirs that it is necessary for them to return to the surface of the water to breathe. Owing to this precaution of nature the Amphibia can wander freely about in the depths of the ocean in search of their food. As their members are badly fitted for locomotion on land, the Amphibia only leave the water when they want to sleep, or while their babies are very young, and feed on the mother’s milk. But these clumsy little fellows soon grow strong enough to dive to the bottom of the ocean with their mother, and search for food among the small Fishes, etc. The Amphibia do not live in very warm regions, and they increase more and more in number in proportion as one advances towards the poles. They are found on the coasts of Europe—in the North Seas, the British Channel and the Mediterranean; and in southern latitudes of the Pacific, along the coast of Southern Chili and upon the shores of New Zealand. THE COMMON SEAL. [Illustration: COMMON SEAL.] The Common Seal, a species frequently seen upon our northern coasts, measures from three to five feet in length, and is of a yellowish grey color, spotted with patches of brown. These animals are met with in greater numbers as we approach the Arctic seas, and afford the principal means of support to the Esquimaux of Labrador, and the inhabitants of the coast of Greenland.