﻿SOME NOTES ON PAPILIONIDS. 227 



the northern portions of its habitat to be double-brooded. Here, 

 on the whole, it may be said to be single- brooded, about eighty 

 per cent, of the first brood going over the winter as pupae after 

 ordinary summers. Even after the exceptionally hot summer of 

 1911 about half my pupae did not disclose imagines till the 

 following year, and this in a season in which, with me for 

 the first time, even viachaon became almost entirely double- 

 brooded. In common with several others of the Papilionids 

 which I have had urder observation, this species in the larval 

 state shows great diversity in the time taken for feedmg-up by 

 different individuals, and half-grown "laggards" may be found, 

 when " forwards " from batches of ova laid at the same time are 

 already pupating. I think that in summers so variable as ours, 

 this should prove a not unfavourable factor as far as the survival 

 of this butterfly is concerned, since it is subject to the attacks of 

 few enemies. As far as I have been able to observe during the 

 last ten years, it is immune from parasites. The minute black 

 ichneumon which infests my butterfly-house, and "stings" the 

 newly-formed pupae of all my other Papilionids, alcinous 

 excepted, leaves philcnor severely alone, and I have never bred 

 Tragus exesoruis, the pest of the Nearctic Papilionids, from any 

 of the pupae received at different times from America. It is free 

 from the ravages of nocturnal foes of an insect kind. Neither 

 earwigs nor Carabid beetles which prey on the young larvae and 

 newly formed pupae of other species, even alcinous, appear to 

 attack it, though I have seen the half-grown larvae bitten and 

 killed by a small green spider which abounds on my Aristolochia. 

 Birds, too, show a pronounced distaste for it. The wild larvae 

 appear to live unmolested on the large plants of Aristolochia in 

 my kitchen garden, and the pupae have survived, though fully 

 exposed throughout the winter, on bushes and the outer wall of 

 a hothouse in the neighbourhood of my butterfly-house. Once 

 when a box containing pupae of this species and P. polyxenes \yas 

 left open by accident in my uncovered butterfly-house during 

 the winter, all the poli/xenes were taken and the iMlenor left 

 untouched. In this case I think that the culprits must have 

 been birds, because the box in question was suspended by a 

 string from the roof of the house, and was out of reach of other 

 possible enemies. Mice, however, will eat the pupae, though 

 they prefer other kinds. In short, I think that this species 

 would stand an excellent chance of establishing itself in the 

 soutbern portions of this country were it not for the extremely 

 hmited distribution of the food-plant, Aristolochia, to which it is 

 confined. In North America it is said to feed upon Aristolochia 

 sipho and A. tomentosa, but of these A. sipho (Dutchman's pipe) 

 is the only one which I have growing here. Unfortunately it 

 does not seem to take readily to Aristolochia clematitis, our only 

 native, or rather naturalized, species, which is found wild in 



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