WHALES, SEALS AND WALRUSES 



which has become adapted to hving in water, but it still 

 retains its mammalian characteristics : for it has warm 

 blood, breathes air with its lungs, suckles its young at the 

 breast, and has the hairy covering possessed (sparsely or 

 thickly) by all mammals. Its tail is not placed vertically, 

 as in fishes, but horizontally — a position which accords 

 better with the animal's need to keep rising to the surface 

 for air. Its external fish-like form is perfectly suited to its 

 life in the sea, but that does not make it a fish, any more 

 than an ape's general resemblance to a human form 

 makes it a man. 



A bat is a mammal, not a bird — it has none of the 

 characteristics of a bird, except its bird-like shape. A 

 great part of its existence is spent on the wing, but it 

 remains a mammal in the air, even as a whale remains a 

 mammal in the sea. 



If the whale was covered with hair, even sparsely, it 

 might interfere with its rapid movement through the 

 water. Its upper-lip and chin whiskers are among the 

 few hairs on its body which link it with mammals of all 

 kinds, from walruses with their bushy whiskers and 

 coverings of short, closely-compressed hair, and polar 

 bears with their thick fur coats. To keep it warm, even 

 in icy seas, the whale has, in place of hair, a thick layer 

 of non-conducting material — its blubber. Its fore-limbs 

 are mere paddles, with little power of motion except at 

 the shoulder joints. But beneath their smooth and con- 

 tinuous outer coverings they possess all the bones, joints, 

 and even most of the muscles, nerves and arteries of the 

 human arm and hand. Buried deep in the interior of the 

 animal, and now quite useless to it, are rudiments of 

 limbs corresponding to the hind-legs of the higher 

 animals. 



Whalers recognize several groups of baleen (or whale- 

 bone) whales, to which they have given such names as 

 right whales, humpbacks, finners or finbacks, and 

 sulphur bottoms, although the latter is really a kind of 



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