550 THE BUTTERFLIES OF NEW ENGLAND. 



uninterrupted emergence of frcyh material from the chrysalis in the north 

 is unknown and needs careful investigation ; but in ^iew of the phenomena 

 witnessed in the neighboring groups it is altogether probable that it is the 

 outcome of a certain degree of lethargy on the }>art of the caterpillar, 

 which would only need to be periodic and fixed in the south, casual and 

 irregular in the north, to produce exactly the phenomena which we see. 

 Experiment and observation can alone settle the question. 



To return to the common history : The eggs — laid upon all parts of the 

 larval food plant — hatch in about a fortnight, and the caterpillars hiber- 

 nate before eating more than their egg-shells, and they rarely devour the 

 whole of these. According to C. G. Barrett, the European species "pass 

 the winter as small social larvae under a silken tent on the ground" (Ent. 

 monthl. mag., xix : 6) but nothing of the sort has been observed on this 

 side of the Atlantic, where they have been raised in greater numbers. 

 Pritcwitz says that the eggs of A. paphia continue through the winter, 

 but it was not so in England with some of this species raised by Mr. 

 Buckler ; it did occur, however, with A. adippe, although it is probable, 

 from his account, that the larvae were fully developed in the egg in the 

 autumn, and merely hibernated Avitliin instead of without the egg. The 

 caterpillars feed singly, and are commonly found upon Violaceae but have 

 also been taken — at least in Europe — on Kubus, Crataegus, Eibes and 

 Urtica, besides several Cruciferae, such as Cheiranthus, Hesperis, Arabis and 

 Dentaria ; as well as on Onobrychis, Plantago and Borrago. They grow 

 very slowly, usually feeding only by night and hiding beneath the leases 

 or in crevices in the ground by day. The chrysalids may be found on the 

 under surface of logs and rails lying upon the ground, and generally continue 

 between two and three weeks. The l)utterflies may be found in the open 

 parts of woods, in fields and hilly pasture land, or skirting the mountain 

 base ; they are exceedingly fond of flowers, particularly of clover, thistle, 

 golden rod and milk weed ; their flight is rapid, strong, prolonged, fre- 

 quently high ; they sometimes sail for short distances with expanded im- 

 movable wings, often then descending slightly in broad circles. 



Characteristics of the early stages. The eggs are short, sugar-loaf 

 shaped, furnished with distinct, rather coarse and rather frequent longitu- 

 dinal ribs and finer transverse raised lines. 



The body of the young larvae is covered Avith little conical warts, 

 ranged on either side in five rows, four above and one below the spiracles, 

 each giving rise to a single, very long, delicately spiculiferous, clubbed 

 bristle. 



The mature larvae are provided with six rows of long, tapering spines, 

 beset with numerous stifle hairs, equidistant as seen in section and radiating 

 like spokes of a wheel ; sometimes one pair on the first thoracic segment 

 is of a different length from the rest ; they are of a dark and rather dull 



