170 



ARTHROPODS : INSECTS. 



year, — one in spring and one in autumn. The females 

 lay their eggs on the young blades of wheat, both in 

 spring and fall. The eggs are only about one fiftieth 

 of an inch in length, pale red, and 

 they hatch in about four days, pro- 

 ducing pale red maggots. The 

 larvae immediately crawl down the 

 leaf till they come to a joint. 

 Here they rest a little below the 

 surface of the ground till they have 

 undergone their transformations. 

 They injure the plant by sucking 

 Fig. 291. -Hessian Fly. j^g g^p. The larvse reach their 

 growth in five or six weeks, and are then covered with a 

 hardening, brown or chestnut-colored skin, and the insect 

 is then said to be in the flaxseed state, from its resem- 

 blance to a flaxseed. In April and May they complete 

 their transformations, come forth in the winged state, 

 and soon begin to lay their eggs upon the spring wheat, 

 and upon that sown the autumn before. The maggots 

 hatched from these eggs pass down the stem as before 

 stated, take the flaxseed form in June or July, and in 

 autumn most of them are transformed into winged 

 insects ; others remain in the ground through the win- 

 ter, and are transformed in the spring, as before stated. 

 These flies sometimes move in immense swarms in 

 search of fields of their favorite grain where they may 

 lay their eggs. The Hessian Fly received its name 

 from the incorrect belief that it was brought to this 

 country in straw by Hessian troops at the time of the 

 Revolutionary War. 



The American Wheat Fly is about one tenth of an 

 inch long, orange-colored ; wings transparent, eyes black 



