ECONOMIC ZOOLOGY 415 



329. Beneficial insects. Many insects are useful from 

 their habit of devouring the noxious species. The lady- 

 bird beetles feed on scale-insects and plant-lice. The ich- 

 neumon flies lay their eggs in the larvae of many species. 

 The carrion-beetles and others are valuable as scavengers, 

 as are various flies. 



330. Animals as servants. As servants of man, the horse, 

 the donkey, the ox, the goat, the dog, the elephant, the 

 camel, the llama, the reindeer, the buffalo of Europe, the 

 water-buffalo of the East Indies, have been with him from 

 the dawn of history, and the help they render needs no 

 description here. 



331. Animals as friends. In the category of higher 

 service to man, the service of friendship, the dog stands 

 nearest. The cat always thinks of herself first, but the dog 

 will lay down his life for his master, or even for his own 

 feeling of duty. The monkey is devoted to his own kind, 

 and may be equally devoted to his master, while his 

 thoughts and disposition run in closer parallelism. But 

 the monkeys for the most part are subject to violent fits of 

 passion over which at the best they have little control. 

 The anger or jealousy of some of the larger monkeys is often 

 dangerous to human life. For this reason men have rarely 

 admitted monkeys to their circle of personal friends. In 

 some respects the gentle, wistful little marmosets of South 

 America constitute an exception to the rule of quick temper 

 among monkeys. To the circle of personal intimacy the 

 dog can often rise, and the horse also so far as he can un- 

 derstand. 



Other friends of man are the singing-birds, those who 

 can be happy even though caged. Easily first of these is 

 the mocking-bird. The bobolink, most joyous of birds, the 

 nightingale, sweetest of all singers, the wood-thrush, and 

 the skylark can scarcely be reared in cages. Other attractive 

 cage-birds are the cardinal grosbeak, the canary-bird, the 

 Japanese finch, and the many species of parrot, who use 



