46 PRIZE ESSAY : 



early sowing, we constantly incur danger from the Hessian fly in 

 tbe fall of the year. If frost occur soon after wheat is sown in 

 the fall, in time to kill the Hessian fly, we rarely suffer much 

 from it. — Onondaga County, N. Y.(i) Wheat more or less in- 

 jured in Kent County, Michigan, when sown before the 20th 

 Septemher.<2) Destructive in Maine, (3) Aristook County. 



Description of the Insect. 



72. Numerous descriptions of the Hessian fly are to be found 

 in scientific and agricultural publications ; in all of the most im- 

 portant features these descriptions coincide. Perhaps the most 

 popular, and at the same time one of the most accurate delinea- 

 tions, is from the pen of the late Dr. Harris, in his admirable 

 " Report on Destructive Insects." 



7Z. " The head and thorax of the fly are black ; the hind- 

 body is tawny, and covered with fine greyish hairs. The wings 

 are blackish, but are more or less tinged with yellow at the base, 

 where also they are very narrow ; they are fringed with short 

 hairs, and are rounded at the end. The body measures about 

 one-tenth of an inch in length, and the wings expand one-quarter 

 of an inch or more. ***** f j^g transformation of 

 some in each brood appear to be retarded beyond the usual time, 

 as is found to be the case with many other insects ; so that the 

 life of these individuals, from the egg to the winged state, ex- 

 tends to a year or more in length, whereby the continuation of 

 the species, in after years, is made more sure."(4) 



74. In the admirable essay on the Hessian Fly, by Dr. Asa 

 Fitch, before referred to, a very exact description of the male 



(1) Address of the Hon. G. Geddes, 1854. 



(2) Pat. Off. Report, 1854. (3) P. O. R. 



(4) I have not lately had an opportunity of referring to Dr. Harris' work, the 

 description given in the text is consequently second hand. 



