The bats are strange looking animals, being half mouse, half bird; their fore limbs are very long, and between these and the hind limbs, and also generally extending to the tail, there is a delicate membrane, which enables them to fly. Their eyes are small; their large ears erect; their teeth sharp. The flight of the bats is swift and noiseless, but not enduring. They could not, like the migratory birds, fly off in the autumn towards warmer countries. Therefore in the winter they retire into clefts and crannies, where they suspend themselves by the claws of their hind feet, and sleep until the rays of the spring sun warm their benumbed limbs. Our native bats feed upon insects, and are consequently useful. In the warm summer evenings they can be seen flitting around the blossoming trees in order to catch the honey-sucking moths. They do not build any nest for their young, but the latter cling between the folds of the wings of the parent animal, and are thus carried about by her on her excursions.
The best known of the foreign kinds are the vampire bat of South America and the colugo bat. In the flying lemur, or colugo, the hairy fold of skin begins behind the throat, includes fore and hind limbs as far as the claws, and extends along the tail to the tip. The animal has been observed to swoop over a distance of seventy yards. The flying lemurs are about twenty inches in length, are natives of the Indian Archipelago, inhabit lofty trees in dense forests, and feed chiefly on leaves and fruits, though said at times to eat insects, eggs, and even small birds. They are nocturnal in their habits, and very inoffensive, scarcely attempting to bite even when seized. Their voice resembles the low cackling of a goose.
THE SEALS (Pinnipedia)
In the seals the five toes of the limbs have become palmate, being joined together by a web; the hind feet have a backward, horizontal direction. Their food consists of small marine animals and plants.
Seal (Phoca vitulina).—The habitat of the common seal is spread over a large area, but it is chiefly found in the northern seas. It is nearly six feet long, and its fur is yellowish grey, sprinkled above with dark-brown spots. It has no exterior ear. To the inhabitants of the north the seal is a most useful animal; its flesh and fat form their chief food, with its oil they illuminate the long winter nights, its sinews they use as thread, from its bones they make various domestic implements, and with its fur they cover their tents and sledges. Seals are gentle animals, and when tamed exhibit great attachment to man. When wounded they snap savagely in all directions. Seal-hunting forms one of the most important branches of commerce among seafaring nations. Over a thousand vessels leave America every year to take part in seal-hunting; and as one vessel will sometimes capture nearly two thousand seals, some idea may be obtained of the immense number of these animals which are slain annually.
Walrus (Trichechus rosmarus).—This animal is from eighteen to twenty-two feet long, and weighs from two thousand to three thousand pounds. It is easily recognized by the long tusks in its upper jaw, which attain a length of eighteen to twenty-four inches.
The walrus lives in the northern Polar seas, where it is sometimes met with in herds of a thousand to two thousand head. They either swim about in the water or lie basking in the sun upon ice-floes. When they are about to sleep one remains awake as sentinel. They [206] attract whole herds to their assistance by their terrific roaring, which can be heard for several miles; in all directions their black heads, with red, dilated eyes, and gleaming tusks, emerge from the water. The walrus is hunted for its tusks, skin and oil.
ANIMALS OTHER THAN BIRDS THAT HAVE LEARNED TO FLY
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| FLYING-FOX WITH OUTSPREAD WINGS. ITS ANCESTORS ONCE WALKED THE EARTHLIKE OTHER MAMMALS | |
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| SQUIRREL-LIKE PHALANGER | |
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| A FLYING FROG | COMMON BAT |
| It glides through air by means of the membranes unitingthe toes, but is not capable of sustained flight. | The bat is the only animal, outside of the birds, thatcan really fly in the true sense. |
Sea Lion (Otaria stelleri).—The home of the Sea Lion is Bering Sea, and as far South as the Kurile Islands on the one side of the north Pacific and California on the other. In the latter case a rookery of sea lions is strictly preserved by the American Government, or probably long ere this the animal would have been exterminated in those waters, as it has been in many other regions after a century and a half of constant persecution.