472 



THE SMALL GRAINS 



from the Atlantic Ocean westward to about 100 longi- 

 tude and southward to approximately 35 latitude, and 

 in a narrow strip along the Pacific Coast from the same 

 latitude 35 to Puget Sound. In Canada it is found from 

 Prince Edward Island to some distance in Saskatchewan. 

 517. Description and food plants. The Hessian fly 

 is very small, about ^ inch long, the body obscurely dark 



in color, and the 

 form much like 

 that of a very 

 small mosquito. 



The abdomen of the 

 female is red or yellow- 

 ish when first hatched 

 from the "flaxseed," 

 the color varying with 

 age, posterior segments 

 terminating in a com- 

 pressed cylindrical, 

 very minutely hairy 

 ovipositor, capable of 

 great extension; the 

 male smaller, more 



slender, and darker in color than the female, the abdomen terminat- 

 ing in a somewhat intricate organ composed of a set of outer and 

 inner claspers (Fig. 148) ; the egg very minute, -^ inch long, cylin- 

 drical, obtusely pointed at the ends, glossy, translucent, slightly 

 reddish, color deepening with development ; larva or maggot when 

 newly hatched smaller than the egg, with a slightly reddish tinge, 

 later, as size increases, at first white, then greenish white, clouded 

 internally by flaky white. After reaching full growth, the larva 

 acquires from its hardened skin a brown covering or puparium, 

 and is then in the "flaxseed" stage (Fig. 149), so called because of 

 the brown color and its more or less flattened shape. From the 

 flaxseed it transforms first to a pupa and from that to an adult fly 

 (Webster, 1915, pp. 2-3). 



FIG. 148. Adult male of the Hessian fly. 

 Enlarged. 



