SOME HABITS OF THE GRAY WHALE 



whale is a very primitive species which is more like 

 its ancient, fossil ancestors than any other existing 

 large cetacean. 



The presence of hairs upon whales and dolphins is 

 evidence that when the animals lived upon the earth, 

 millions of years ago, they must have been entirely 

 covered with hair as are ordinary land mammals. 

 The hair of most whales is confined to the snout and 

 chin but in the devilfish it is distributed in irregular 

 rows over the top and sides of the head. 



The hair on cetaceans is in a degenerate condition 

 and does not possess at the base a gland (sebaceous) 

 for the secretion of oily matter to supply it with 

 nourishment and lubrication as in land mammals. It 

 seems probable that the loss of hair in cetaceans is 

 largely due to their aquatic life, because the blubber 

 performs the function of hair in keeping the animals 

 warm and an outer covering is no longer needed; 

 also most land mammals need hair to protect their 

 tender skins from bruises and abrasions but for a 

 whale this is unnecessary. 



The manatee, or sea cow, an entirely aquatic mam- 

 mal, has lost nearly all hair, and in the walrus it has 

 become very much reduced; the latter animal spends 

 almost all its time in the water, coming out but com- 

 paratively seldom to sleep upon the smooth ice; and 

 in addition to the blubber it has developed an exceed- 

 ingly tough skin. It is true that seals all possess 

 blubber, and some an additional coat of thick soft fur, 

 but they are not as yet exclusively aquatic; although 

 much of their life is spent in the water, they still come 



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