54 



A FEW WORDS ABOUT MOTHS. 



in the winged state. Still a larger proportion of insects are 

 directly beneficial from their habit of attacking injurious spe- 

 cies, such as the ichneumons (Fig. 43, the ichneumon of the 

 American silk worm) and 

 certain flies (Fig. 44, Ta- 

 china) ; also many carniv- 

 orous species of wasps 

 beetles and flies, dragon 

 flies and Aphis lions (Fig. 

 45, the lace -winged fly; 



Tachina, parasite of Colorado Potato 

 Beetle. 



adult, larva and eggs). 



But few, however, sus- 

 pect how enormous are the 

 losses to crops in this coun 

 try entailed by the attacks 

 of the injurious species. 

 In Europe, the subject of 

 applied entomology has al- 

 ways attracted a great deal of attention. Most sumptuous 

 works, elegant quartos prepared by naturalists known the world 

 over, and published at government expense, together with 

 smaller treatises, have frequently appeared ; while the subject 



is taught in the nu- 

 merous agricultural 

 colleges and schools, 

 especially of Germa- 

 ny- 



In the densely pop- 

 ulated countries of 

 Europe, the losses oc- 

 casioned by injurious 

 insects are most se- 

 verely felt, though 

 45. The Lace-winged Fly, its Larva and Eggs. fj-Qm m a n V causes 



such as the greater abundance of their insect parasites, and the 

 far greater care taken by the people to exterminate their insect 

 enemies, they have not proved so destructive as in our own 

 land. 



In this connection I may quote from one of Dr. Asa Fitch's 

 repoi'ts on the noxious insects of New York, where he says : "I 

 find that in our wheat- fields here, the midge formed 59 per cent. 



