198 THE CANADIAN ENTOMOLOGIST. 



dently sown by mischievous persons receiving live specimens through the 

 mails. In the Moths, the wood-boring species may be introduced by 

 accident, but, unless in such cases as the Currant Clear Wing (Aegeria), 

 such an introduction would be usually futile for the establishment of the 

 species. Specimens of the Wood Leopard, Zeiizera Aesculi, are said thus 

 to have been found about New York, and even the Goat Moth, Cossus 

 Lignipcrda, is stated to have been so found. Again, in Wood's " Index 

 Entomologicus," are figures of one or two of our Noctuidae, the originals 

 of which; if authentic, must have been accidentally introduced into Eng- 

 land, and disappeared again without leaving progeny behind them. One 

 or two cases have fallen under my notice where deception has evidently 

 been intended, but the naturalist, from his knowledge of the habits of the 

 insect, will quickly detect such frauds. One case of reported identity I 

 regret not to have been able to verify. It is that of the European Cato- 

 cala Nupta, said to have been found on Long Island. Now the genus 

 Catocala is peculiar to the Northern Hemisphere, and our species and the 

 European have undoubtedly a common ancestry. But the remarkable 

 fact is that our forms have differentiated widely and multiplied exceed- 

 ingly, so that we have fresh Groups and a much greater nimiber of species 

 compared with Europe. That, therefore, one form of Catocala should 

 have remained constant is, to me, incredible, and I shall prefer to believe 

 that the reported American specimens of C. Nupta are the result of recent 

 importation or of deception. We have witnessed the acclimatization of 

 the Chinese Silk Worm, Fhilosatnia Cynthia, on the Ailanthus trees in 

 the vicinity of New York and Philadelphia, and, in the case of the Spin- 

 ners, cocoon-making species, it seems likely that the wholesale transference 

 of such species in the pupal state would result in the permanence of the 

 form in the wild state in the new locality. But the very difficulty which 

 generally attends the introduction of new species into a fresh locality, 

 suggests that most of the species common to America and Europe have 

 simply remained unaltered since prehistoric ages. The pattern of orna- 

 mentation has remained constant, while Dr. Speyer has noticed a shading 

 or quality in the colors which renders the specimens still distinguishable 

 by the practised eye, and which is evidently due to the differences in light 

 and humidity. But, as in the case of Catocala Nupta, the naturalist will 

 have to take into consideration the whole range of special facts to decide 

 any one case where historic evidence is totally wanting. 



