48 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, 84 



iinthreshed wheat brought to the port of Quebec and was noted as 

 destructive in the northwestern part of Vermont in 1828. From that 

 time it had spread itself all over the " free States " and Canada as far 

 west as Michigan and Indiana. The remedy recommended was burn- 

 ing the screenings or feeding them to poultry or swine. He described 

 no certain parasites, and suggested the importation of the European 

 parasites since the wheat midge had been known for years in Eng- 

 land and had only recently appeared in France ; in fact he wrote to 

 Curtis in England on this subject, who advanced the proposition at 

 a meeting-of the Entomological Society of London. So far as I know, 

 however, there were no results. Other insects treated in this report 

 are the grain aphis and the army worm. 



One sentence in this report is striking. After stating that the 

 wheat midge was at that time causing loss to the State of New 

 York of some millions of dollars annually, it goes on to say, " and 

 this loss wull continue until by accident or by the hand of man the 

 parasitic destroyers of this insect become introduced into this coun- 

 try, when it will disappear, in the same manner that its predecessor 

 and compeer in destructiveness, the Hessian fly, has disappeared and 

 has almost ceased to be felt as an evil." 



It is true that the Hessian fly ceased to do serious damage in 

 New York a little earlier than that period, and the later enormous 

 ravages of this species which have continued from time to time until 

 the present have been felt in the great wheat-growing regions far- 

 ther west ; only, however, in regions of winter wheat. It is possible 

 that the lessening of winter wheat in New York and the growing of 

 spring wheat instead, brought about this disappearance of the Hes- 

 sian fly in injurious numbers commented on by Fitch. 



But what is the explanation of the subsequent disappearance of the 

 wheat midge, which in Fitch's time was so enormously destructive? 

 Was there a change in cropping methods ? Was there a general adop- 

 tion of some resistant variety of wheat? Or did the insect parasites 

 of native Cecidomyiids take to the wheat midge and control it even- 

 tually almost to the point of extermination? These are interesting 

 questions which it will be very well to make an effort to solve in viev/ 

 of other things that have happened since.^ 



This sixth report is prefaced by two lithographed plates, one 

 devoted to the midge and the other to the Angoumois grain moth, the 

 grain aphis and two species of parasites. The drawings were made by 

 Doctor Fitch and are very good. 



' Doctor Felt has the opinion that the so-called " Wheat Midge " of this country 

 is not specifically identical with the old Diplosis tritici of Europe. 



