586 THE BUTTERFLIES OF NEW ENGLAND. 



Later observations, however, show that this cannot be the case, and it is 

 even contended by Mr. Edwards — and on the basis of his own experiments 

 alone quite justly — 1°, that our species are triple brooded, one brood fol- 

 lowing another with perfect regularity ; 2°, that the eggs are always laid 

 by females fresh from chrysalis ; 3°, that the caterpillars are not lethargic 

 in the warm season ; and 4°, never Avinter immediately after leaving the 



Mr. Edwards's observations were made almost entirely on B. myrina ; 

 my own and that of my correspondents mostly on B. bellona ; but it is 

 hardly so probable that the two species differ markedly in their life his- 

 tories as that the history of either of them may vary under changed circum- 

 stances, or even in what appear to be identical circumstances, as was the 

 case with B. euphrosyne, under the eyes of Vaudouer. For in contradis- 

 tinction (but not necessarily opposition) to Mr. Edwards's conclusions I 

 have observed that not only females fresh from the chrysalis, but those 

 which must have been flying several weeks, often have the eggs in their 

 bodies quite undeveloped ; that caterpillars are often lethargic in the warm 

 season, the phenomenon having been observed in several lots in two differ- 

 ent summers ; and that caterpillars hatched in September, and even early 

 in September, may very often hibernate directly from the egg. 



My conclusion from all the facts now at hand is that the butterflies 

 should be regarded as partially triple, partially double, and possibly par- 

 tially single brooded. They fly first in May and June, and thereafter 

 until the middle of September may be found on the wing without break, 

 though their numbers are notably reinforced by fresh examples in the lat- 

 ter half of July and toward the end of August. No eggs are known to be 

 laid by the first brood until the middle of June, two or three weeks at 

 least after the appearance of the brood. Some, certainly, of the caterpil- 

 lars from these eggs develop to form the second flight of butterflies toward 

 the end of July; perhaps all do, as no lethargy has yet been observed in 

 the caterpillars of the spring brood ; yet, as it has been observed in the 

 corresponding brood of B. euphrosyne in Europe, it is altogether probable 

 that we shall find it here and discover that such lethargic caterpillars may 

 swell the third brood of butterflies, or even the first brood of the succeed- 

 ing year; for the third brood certainly, and the first also, I am inclined to 

 think, is always more abundant than is the second. Eggs of the second 

 generation are laid in the latter half of July and early in August ; they 

 are sometimes fully formed on eclosion of the female of the second brood, 

 and sometimes they are not ; sometimes they may be still undeveloped in 

 butterflies which have evidently flown several weeks ; but on the other 

 hand, Mr. Edwards has obtained eggs from butterflies not thirty-six hours 

 old. The caterpillars from these eggs may or may not become lethargic 

 when partly grown, and the lethargic caterpillars may arouse before the 



