1100 THE BUTTERFLIES OF NEW ENGLAND. 



spots ; tlic fore wing has a black spot at the tip of the coll above, repeated 

 beneatli, with a pale or silvery pupil ; and the hind wing has a larger cen- 

 tral spot, faint orange or obsolete above, silvery, dark edged and some- 

 times double beneath ; the under surface resembles the upper except in 

 these particulars, in wanting the black border and in being frequently 

 flecked with green. The butterflies may be distinguished from all our 

 other nortliern Pierinae by the absence of paronychia. 



There is probably not another group of buttei-flies about the different mem- 

 bers of which, at least in this country, there has been more dispute or more 

 varied opinions held. Fortunately for our present consideration these ques- 

 tions hardly arise, the three species here discussed being very certainly dis- 

 tinct, though no doubt nearly allied. 



These insects are single brooded in the alpine, arctic and subarctic 

 regions, double brooded in Europe and triple brooded in the United States. 

 The European species are all said to hibernate in the chrysalis state,* 

 while the single brooded forms have been supposed to winter either as eggs 

 or chrysalids. The former is in no degree probable, for the eggs are of 

 such a form and stru<!ture as could scarcely brave the perils of winter, and 

 are laid upon the leaves of the food plant. Doubleday says that a few 

 individuals probably hibernate as butterflies, but it is probably upon the 

 endurance of the caterpillar that the existence of the species depends. 

 The caterpillars live singly and mature rapidly, the species of the tem- 

 perate regions feeding on papilionaceous Leguminosae, while the alpine 

 E. palaeno feeds on different species of Vaccinium (Ericaceae). The 

 butterflies are somewhat swift in flight, especially when alarmed, but they 

 do not usually rise more than three or four feet above the ground. They 

 frequent the open country. The North American species, says Doubleday, 



are extremely fond of ali<;htiug on moist sand or mud. By the side of ponds and 

 brooks, tlirougliout tlie nortiiern and middle states, and on the large mud Iioles not 

 very rare iu the roads of Ohio and Illinois, I have seen them assembled literally by 

 hundreds. In the northern states it is only Colias philodice which occurs, but in the 

 middle and western states the assemblage is composed also of Colias coesonia, Calli- 

 dryas marcellina, Terias nicippe and Ter. lisa. These assemblies are so closely packed 

 that rows of forty or fifty individuals maybe seen, their wings closed over their backs, 

 their aides actually touching one another. Sometimes the group is augmented by a few 

 noble specimens of Papilio turnus, P. troilus, P. philenor and P. asterias, with the 

 addition of some large fritillaries and perhaps that beautiful little blue, Lycaena 

 comyntas. These companies, when thus met, are very reluctant to disperse, and are 

 rarely disturbed by a mere passer by. When tliey do all rise together, the sight is 

 beautiful in the extreme (Gen. diurn. Lep., i ; 73). 



Sometimes great clouds of these butterflies have been seen on the wing, 

 the most interesting account of which is the one given by Darwin which 

 we have elsewhere quoted. 



The eggs are subfusifonn in shape, longitudinally ribbed and attached 

 at one end : they hatcli in a very short time. 



*Long claims that E. edusa hibernates as an iinaso. 



