204 THE entomologist's recokd. 



in the course of the year, has proved the easiest of all to cope with in 

 this respect. 



Pap'ilio{Jasonia(les)(flaiiciis («»/»//*) is said by American entomologists 

 to be single- brooded in the extreme northern parts of its habitats, yet, in 

 1906, the larvae which I bred in my butterfly-house, in spite of being 

 removed to a specially cold, well-thatched, apple-house immediately 

 after they had spun up for pupation, without exception, produced 

 imagines early in September. Again last year, cold and Avet as the 

 season was, I was unable to induce any of my ,/. (/laiicKs pupae to go 

 over to the winter, but the butterfly obstinately kept on coming out 

 until well on into November. I do not think that the pup^ from 

 which my J. ijlaucus are bred come from the extremely southern part 

 of the range of this species, as, on an average, the black females are 

 only in the proportion of one to four to the yellow ones. With regard 

 to Scudder's statement that some of every brood of this species go over 

 the winter as pupffi, I can only say that I have never yet had one of 

 the first brood that did so, though, of course, the number of pupae I 

 have been successful in bringing through at present has not been 

 large. 



On the other hand, having succeeded for the first time in getting 

 some of the foodplant of Kiiphoeades troilns for my butterfly-house 

 last year, I managed to rear about three dozen pupae of this species. 

 Now these, in spite of being left out-of-doors and exposed to whatever 

 sunshine there was until the middle of October, one and all went over 

 the winter, the butterfly being at least double-brooded in its natural 

 habitat, and a denizen of a more southern part of the United States, 

 upon the whole, than Jamniades glaticus. 



With Pai)ilic pnlyxenes (asteriafi) my experience has been exactly 

 the reverse, and, on the only occasion upon which (1905) I reared a 

 large quantity of this species, the whole of the pupae of the first brood 

 gave rise to imagines early in August, and I was able to feed up a second 

 brood, Avhich all hybernated as pupte. 



But it is with Laertias philenor, a butterfly of which I breed a fairly 

 large quantity every year, that my experience has been strangest. 

 According to Scudder and other American entomologists this species 

 produces several broods in the year in America. It is said to oviposit 

 even as late as October. It is the only representative of the great 

 tropical family of pharmacophagous Papilios in the United States, and 

 one would expect (it being a southern butterfly which has spread its 

 range northwards, not, as in the case of J. ijlaucus, a northern butterfly 

 which has spread its range southwards) that its habit of producing more 

 than one brood, would be deeply ingrained in it. However, this is so far 

 from being the case, that, in spite of my not collecting the pupae of this 

 species till October, never more than from about three to fifteen per 

 cent, (according to the warmth or otherwise of the early autumn) 

 produce imagines, but here, at least, it becomes practically a single- 

 brooded species under natural conditions. It seems to me that this 

 extraordinary difference in responsiveness to environment must prove 

 an important factor in the survival or non-survival of species at times 

 of great climatic changes in the earth's history, and I thought it worth 

 drawing attention to in consequence. 



