GENERAL ECONOMY OF INSECTS IN NATURE. 15 



the agriculturist; whilst the 

 tribes of insects which feed 

 upon decaying vegetable mat- 

 ter are even still more nume- 

 rous. As serving for food to 

 some of the higher animals, as 

 fish, birds, some of the smaller 

 mammalia, &c., insects are emi- 

 nently serviceable in the scale 

 of the creation. Amongst birds, 

 the shrikes, and the genera 

 W' Motacill^Anthus, Cer- 

 thia, Muscicapa, and Hirundo, 



as well as the cuckoos and pies ; and amongst quadrupeds, 

 the genera Stenops and Otolicnus, which feed upon grass- 

 hoppers, the bats, shrew, hedgehog, mole, and especially 

 the genus Myrmecophaga, derive their sole nutriment from 

 insects. Many species of insects are equally serviceable 

 in destroying other noxious insects. Of these the tribes of 

 predaceous beetles, sandwasps, ants, dragon-flies, spiders, &c., 

 are to be noticed, but more especially the larvae of the lady- 

 birds, Syrphidce, and golden-eyed flies, which destroy myriads 

 of plant lice. All these, however, yield to the Ichneumonidce, 

 which annually destroy more caterpillars than the whole tribes 

 of insectivorous birds, having almost universal dominion over 

 the other insect tribes. In the last place, we have to notice 

 the great services rendered by insects in effecting the im- 

 pregnation of plants, in many of which the position of the 

 sexual organs is such, that the intervention of insects, 

 especially bees, butterflies, &c., is required, which, whilst 

 seeking food for their own nourishment, unconsciously per- 

 form this most important office ; whilst some of the Cynipida 

 effect the more rapid ripening of the fig, by the process 

 termed caprification by the inhabitants of the Levant. 



