NYMl'HALINAE : THE (iENUS r.RENTIIIS. 587 



end of the season and resume feeding, or tliey may not, but instead extend 

 their lethargy to liibernation, and enhu-ge the spring brood of butterflies. 

 Tlie third laying of eggs takes place the last ten days of August and in 

 September, and these eggs are laid partly by fresh females, partly by butter- 

 flies of the second brood which have been on the wing until they are 

 ragged and torn to the last degree ; and, as in the case of the second 

 brood of butterflies, some of those belonging to the third brood are in no 

 way ready to lay their eggs when they are born, the eggs being developed 

 in their ovaries only as mere pin-points. At the end of August, therefore, 

 we have a very heterogeneous assemblage, — eggs laid by butterflies of the 

 second and of the third broods; caterpillars just born, from eggs of two 

 broods of buttei'flies ; caterpillars partly grown and active, from eggs laid 

 by butterflies of the second and perhaps of the first brood ; caterpillars 

 half grown and dormant, from eggs laid by the same ; chrysalids from 

 butterflies of the same ; and butterflies fresh and worn according as they 

 belong to the third or second brood. The caterpillars from the last batch 

 of eggs may feed until partly grown and then hibernate (Mr. Edwards's 

 observations), or they may hibernate at once on hatching, and it is not 

 impossible, from what I have seen, to believe that they may winter in the 

 >'gg as fully formed caterpillars. 



These general remarks, it should be said, do not necessarily include any 

 other American species than B. bellona and B. myrina ; it is believed that 

 they have equal reference to both of them, though they are sometimes 

 founded almost entirely on observations on only one of these species. 



The early stages. In our American species, the eggs, often, as 

 already stated, not laid until several weeks after the eclosion of the butter- 

 fly, hatch in about a week. The caterpillars are lively and timid, lying 

 concealed by day and feeding by night, principally on violets, but also on 

 Arabis, Trifolium? Hedysarum, Fragaria, Spiraea, Sanguisorba, Rubus, 

 Primula, Polygonum, Urtica and Anchusa, and possibly grasses. 



The chrysalids hang from seven to ten days. The butterflies are par- 

 tial to meadow land, wooded fields or open thickets ; some species are con- 

 fined to mountain slopes clothed with a low and scanty vegetation. 

 Doid)leday, comparing them with the species of Argynnis, says they are 

 insects of slower and weaker flight, rarely rising to any height, and more 

 frequently returning to the same spots ; they may often be seen coursing 

 backward and forward along some marshy bit of ground. When the 

 buttei'flies are at perfect rest, the wings are closely shut, the front pair 

 concealed as far as possible ; when expanded, these are brought well for- 

 ward. The antennae usually diverge at about right angles. 



The eggs are short, sugar-loaf shaped, a little constricted on the upper 

 part, furnished with ribs and transverse ridges, as in Argynnis. 



The body of the juvenile larvae is covered with little conical warts 



