412 ANIMAL STUDIES 



whale aiid other large whales. These whales also yield 

 whalebone from structures used in straining out their food 

 developed on the roof of the mouth. Finer oils come from 

 the sperm-whale, the most valued being a wax-like sub- 

 stance, spermaceti, found in the head. Ambergris is an 

 abnormal secretion sometimes found about the liver of the 

 sperm-whale. It has a very high value, being very fragrant 

 and used as a perfume. The old-fashioned perfumery 

 musk is a secretion of the musk deer ; civet is produced by 

 the Viverra, a weasel-like animal of South America. 



Ivory comes from the tusks of the elephant. The long 

 teeth of the walrus are very similar to true ivory. 



The horns and bones of different animals have many 

 uses in the arts. The quills of l)irds have also certain uses. 

 The scales of sea-tortoises are used in making combs. 

 The coloring-matter, cochineal, much used before the in- 

 troduction of anilin dyes, came from the bodies of certain 

 scale insects living on cactus, chiefly in Mexico. 



324. Animals as enemies and destroyers of enemies of 

 man. The chief enemies of man are the larger carnivorous 

 animals which are personally dangerous to him, to his 

 flocks, or to his crops. Among these are the great wildcats 

 (lion, tiger, leopard, panther, etc.), the wild dogs (wolf, 

 coyote, jackal, etc.), the rodents (rabbits, rats, mice) which 

 devour his crops or his stores, and the great multitude of 

 insects which destroy his crops. 



Against the great carnivora, the dog, itself a tamed 

 wolf, is his best defender. The dog, cat, ferret, and mon- 

 goose have been brought into his service as destroyers of 

 rodents; the mongoose, by destroying lizards and birds' 

 nests also, doing more harm than good. The hawks, owls, 

 and snakes also help him in keeping down the numbers of 

 rats and mice. 



Against the hordes of noxious insects man's chief natural 

 protection is found in the singing-birds, most of whom feed 

 on insects which destroy vegetation. He has also a large 



