This history of the Hessian fly agrees closely with that of tin 
wheat buib worm, which insect is now also known to be ungues 
tionably three-brooded. The period of the second brood coincides 
almost exactly with that of the Hessian fly, the third brood agreeing 
also, except that it is somewhat retarded in its later stages, hibernatl 
ing only as a naked larva, and not reaching the imago stage nntij 
nearly a month later, on an average, than the corresponding 
stage of the fly. The first brood of the JNIeromyza is corresponds 
ingly later than the other in its origin, but passes through its 
tiansformation more rapidly, development from the egg to th! 
imago occurring, so far as our observations show, within the 1 limit! 
oHa single month. 
