( 14 ) 



examination they appeared to me to be nineteen in 

 number, that is 2 plus 17. The colour altered with 

 change of condition of the specimen, but might through- 

 out be called brown. 



The above account refers to the condition of the 

 specimen whilst still not quite dead, about eighteen hours 

 after the first observation. Twenty-four hours later the 

 raspberry tints were changing to shades of brown or 

 yellowish brown, and the black velvety patches at the 

 sides of the abdomen were scarcely distinguishable from 

 the transverse bands. The changes in colour continued, 

 till on the third day from the first observation the rasp- 

 berry tints had changed to dark brown above, lighter or 

 yellowish brown below, the terminal segments and the 

 ovipositor still retaining the original tint of yellowish 

 brown. 



From minute examination of structure and comparison 

 with the descriptions and figures in the works cited, 

 the imago appeared to me to be without doubt the 

 Cecidomyia destructor of Say, commonly known as the 

 "Hessian Fly." 



In an attack of this importance, regarding which it is 

 yet to be seen whether it will settle in the land as a 

 national scourge, or be a temporary infliction from 

 causes not yet made out, I in no way desired to rest 

 solely on my own opinion. I therefore submitted 

 infested straw to Professor Westwood, Life-President of 

 the Koyal Entomological Society, who is personally 

 acquainted with the insect in the " flax-seed " as well as 

 in the perfect state, and also forwarded others to Prof. 

 W. Saunders, President of the Entomological Society of 

 Ontario, Canada, a well-known and most sound authority 

 in the matter, and received from both the above referees 

 the confirmation that the specimens sent were without 

 doubt the pupae of the true Hessian Fly. On the 

 appearance of the imago I submitted it for special 

 examination to Mr. E. H. Meade, of Manningham, 

 Bradford, whose researches on the Diptera are too well 

 known to require any comment, and had from him the 



