6 



BRITISH BUTTERFLIES. 



" The species of Basilar chia are the only ones among New England 

 butterflies which construct hybernacula, properly speaking, i.e., nests 

 for the special purpose of wintering in them, and which they use at no 

 other time ; here, each individual makes for itself its separate nest. 

 Euphydryas, however, alters and strengthens its social nest for the 

 winter to such an extent that its appearance is then quite different, 

 and, in the centre, as the nest contracts with the withering of the 

 leaves, the caterpillars are crowded together into an almost solid mass. 

 The other larger caterpillars, which make no nest, probably seek merely 

 some cranny upon or near the ground wherein to lie concealed during 

 the winter." We cannot support the whole of Scudder's statement here 

 given from the Palaearctic species known to us. With the exception of 

 the " skippers," which spend their larval life in folded tubular leaves, 

 the gregarious Melitaeids, and Aporia crataeyi, we cannot call to mind 

 any species that forms a winter nest, except Limenitis sibylla, which has 

 very similar habits in this respect to the American Basilarchia species, 

 e.g., B. archippus (see Butts. New England, i., p. 274), B. artliemis 

 (op. cit., p. 301), etc. None of our hybernating Ruralid (Lycamid) or 

 Satyrid larvae do so, and these, at least in our western Palaearctic area, 

 form a large percentage of our larva-hybernating butterfly species. 

 Of this fact, at least so far as it relates to the Argynnids and Satyrids, 

 Scudder seems, in spite of his statement, to have been fully aware (see 

 antea, p. 3). The winter-nest of Melitaea cinxia appears to be a 

 somewhat strengthened and better-hidden form of the feeding autum- 

 nal nest, in the former respect, perhaps, resembling that of Euphy- 

 dryas phaeton. The latter, by the time the larvse have passed their 

 third moult, is sometimes llins. x4ins. in extreme length and 

 width, sometimes considerably smaller. Edwards describes a large 

 one as "long and narrow, tapering at either end, about 3ins. broad 

 in the middle, and so thick and closely woven as to conceal the 

 interior. For egress while at work, two somewhat tubular openings 

 were left on the middle of one side, and the threads about these were 

 doubled. To support this large web the upper part of a stem of 

 swamp grass .... was bent down, and its broad and spreading 

 leaves were bound over the surface, and this, with the stem of Ohelone, 

 was stiff enough to resist the wind. After the larvse had ceased work 

 and finally retired within the web, a slight covering was spun across 

 the outlets, sufficient, evidently, to throw off water and to keep out 

 spiders .... Six weeks later the webs were found to be 

 bleached white, and were weather-worn and considerably shrunken, 

 often distorted, too, by the growth of the plants. The effect of the 

 shrinkage was to compress the larvaa into a hard, compact mass." 

 Strangely enough, Cinclidia harrisii, another North American Melitreid, 

 is said by Scudder (op. cit., i., p. 681) to form larval nests like E. phaeton 

 when young, but he adds that the. larvae desert these nests before 

 hybernation, probably passing the winter in curled-up dead leaves, or 

 beneath sticks and logs. 



The phenomenon of hybernation, as here detailed, most probably 

 had its origin in a reaction to low temperature and want of food, and 

 even now, in many cases, shows distinctly its relation thereto, but it is 

 really remarkable that some larva 1 , hatching in early or middle 

 summer, should at once, e.g., Dryas papliia, Argynnis a(/laia, com- 

 mence to hybernate, or feed up only a very short time before doing 



