244 



THE MONTHLY BULLETIN. 



ciently to cause serious damage in one year. A cultivated crop once 

 in two or three years as a rotation with clover or alfalfa is recommended 

 when the destructiveness of the pest warrants strict remedial measures. 



Natural Enemies. — Carnes and Newcomer report a tachinid fly as 

 parasitic upon the larvfe. 



THE HESSIAN FLY. 



Mayetiola destructor (Say) (Family Cecidomyiidse). 



(Cecidomyia destructor Say.) 

 (Fig. 241.) 



General Appearance. — This insect when fully developed is a small 

 brown fly about one tenth of an inch in length. The eggs are about 



Fig. 241. — The Hessian fly, Mayetiola destructor 

 (Say). Healthy wheat stock at left and infested stock 

 at right ; a, egg ; h, larva ; c, puparium or "flaxseed" ; d, 

 pupa exposed ; e, adult female laying eggs ; f, female ; g, 

 male ; li, puparia or "flaxseed" in natural position be- 

 tween leaves and stalk; i, parasite {Merisus destructor). 

 (Slightly enlarged, excepting e, which is smaller than 

 natural.) (After Riley, Burgess and Forbes.) 



