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SECOND ANNUAL REPORT OF 



THE GRAPE SEED-MAGGOT— Isosoma vitis, Saunders. 



(Ilyinenoptera, Chalcididic.) 



In my First Report (pp. 125-31), I gave an account of a minute 

 maggot (Fig. 64) which had been found by Mr. Wm. Saunders, of Lon- 

 don, C. W., to infest the seeds of growing grapes, 

 and to occasion much damage around London and 

 .Paris, by causing the berries of the Clinton, Dela- 

 ware, Rogers' No. 4, and some of Mr. Arnold's Seed- 

 lings, to shrivel up without maturing. There are so many noxious 

 insects, common in Missouri, that occur also in the southern portions 

 of Canada West, that it was deemed necessary to give the grape- 

 growers of the State a diagnosis of its work, in case it should at any 

 day make its appearance in our vineyards. 



From the appearance of this maggot, I inferred, with every one 

 else who gave an opinion, that it would most likely produce some 

 small species of snout-beetle (Curculio family). Now mark how 

 dangerous a thing it is, for even an entomologist to guess at the char- 

 acter of some insects, when in this masked form. We flatter our- 

 selves that there are but very few insects among the half million dif- 

 ferent species that are estimated to exist in the whole extent of this 

 terrestrial globe of ours, that we cannotplace at a glance in its proper 

 Order, even when in the larva state; but let us humbly acknowledge 

 that there are some few larval forms among the more minute Four- 

 winged Flies (order Hymenoptera) and Beetles (order Coleoptera) 

 which it is almost, if not absolutely, impossible to distinguish the 

 one from the other. 



Last August I had the pleasure of spending a few hours with Mr. 

 Saunders, at his place in London, and I was gratified to learn that he 

 had bred the perfect insect from this seed-maggot. It proved to be a 

 little Four- winged fly ( CJialcis family), and upon my return home, I 

 found a few specimens of the very same species of fly, in a bottle in 

 which were placed some infested grapes received the year before 

 from Mr. A. S. Fuller of New Jersey, and obtained by him from Canada. 



[Figf. 65.] 



This fly so closely resembles 

 the notorious Joint- worm Fly (Iso- 

 soma Aordei, Harris) that the ac- 

 companying highly magnified 

 sketch (Fig. 65) of that insect — a 

 representing the female, h the 

 male, c the? antenna, d the J do., 

 e the $ abdomen and ft\\e $ do. — 

 will afford a very correct idea of 

 its appearance. 



The Grape Seed-maggot Fly 

 differs principally from the Joint- 

 worm Fly in its somewhat smaller 

 size, in the legs being marked 



