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 explain some of our phenomena, but there is much need for precise measurements and bio-chemical investigations on our particular winter-active species. Concerning European Cynips Kieffer (1901:632) devoutly remarked of the insect which had delayed its emergence: “Ce qu'il attend, c'est l'époque que la Nature lui a assignée.”

Whether the emergence date is determined by the response of the insect to environmental factors should be determinable by modifications of those factors. This experiment we have conducted on an extended scale, incidental to the breeding of Cynips material. We have brought 60 of the species of this genus from every type of remote locality to breed out-of-doors under the peculiar conditions of southern Indiana winters. We have bred material from northern Michigan and the mountains of northern California, from southern Georgia and the Gulf Coast, from southern California, Denmark, and more southern Europe. In many cases we have bred the same species for several winters, and in the case of Cynips fulvicollis (detailed later) we have had to keep transplanted material for two and three years outside our laboratory windows before the insects matured. Nevertheless, in all of this work, we have secured emergence at dates that would have been normal in the native habitats of the species. The season of emergence has been shown to be a specific quality which is not dependent upon the responses of the individual insects to immediate environmental conditions.

Northern Michigan material of Cynips pezomachoides wheeleri, due to emerge in northern Michigan during cold weather in late November and early December, emerged in southern Indiana at those same dates, altho at that season the temperatures are still very mild in our part of the country. Material of Cynips pezomachoides pezomachoides from near Boston, Massachusetts, emerged at Boston late in November and early in December at temperatures ten or fifteen degrees below freezing, while our material of apparently the same insect from the Carolinas, Georgia, and northern Florida emerged at the very same dates during mild weather in southern Indiana. We have had similar experience with several varieties of Cynips fulvicollis and still other species of the genus. The data for fulvicollis are: