70 



THE ENTOMOLOGIST S RECORD. 



ning of September, except a few species with very long graduated 

 emergence, and also Hesperia inalvoides which emerge in anticipation 

 at the beginning of spring and at the end of July, and some Vanessidi, 

 which emerge later at the end of June and in September or October. 



(3) In the case of three broods the first emerges in the first half of 

 spring, the second at the beginning of summer, and the third at the 

 end of August and in the first half of September. 



These periods of emergence remain almost fixed in all the regions 

 in which the greatest number of broods are produced, and the variations, 

 of altitude and latitude only influence the duration of the period of 

 emergence by lengthening or shortening it, chiefly in the first brood. 



We arrive, therefore, at two general conclusions, all the more 

 interesting in that they were unexpected : — 



(1) The maximum number of ordinary annual broods vary in the 

 Gri/pocera and Rhopalocera from one to three, according to the species. 



(2) Some species, which emerge in an almost continuous manner 

 during all the good season and have apparently an indefinite number 

 of broods, have in reality only two. 



The following examination of the different types of emergence and 

 their modes will serve better to clear up and illustrate these conclu- 

 sions. The most notable difference among the various modes of emer- 

 gence consists in the variableness of the duration of each brood in the 

 different species ; in this respect there are two principal types to be- 

 distinguished : a. In one all the families of the same locality emerge 

 almost at the same time during a period which varies according as the 

 individuals which compose it emerge, almost contemporaneously, or 

 gradually ; thus some species emerge in a m^jss during a few days, and,- 

 although the numbers of individuals may vary from year to year, the 

 days of the year remain always the same with an almost incredible 

 constancy. Cnpido sebrus, for example, emerges in Florence from the 

 10th to the 20th of May, At/riades escheri, Hiib., from the 6th to 

 the 16ch of June, etc. Other species, instead, emerge during a relatively 

 Ipng period ; thus, the males of Epi)iepliele jurtma, L., appear in the 

 perfect state froin the end of May to the end of June, and the females 

 from the middle of June to the end of July ; in other cases, again, one 

 observes a relatively short period in which the mass of individuals (the. 

 " nucleus " of the brood) emerge, another preceding and another follow- 

 ing, more or less long, during which a much smaller number of indi- 

 viduals (" sporadic — precocious " and " sporadic — tardy ") emerge ; the 

 precocious individuals are nearly all males ; for example, the third 

 brood of Colias croceus,''- Fourc, and that of Bniiiicia phlaeas, L., 

 fly in September, but sporadic individuals appear from the first days of 

 August; Satyrus major {hermione ? — G.W.), Esp. ; is properly of July, 

 but appears sporadically from the end of May ; Lampides boeticiis, L., and 

 Raywardia telicanus, Lang, belong properly to September, but some 

 individuals are seen from the end of June ; the first brood of Agriades 

 thetis, Eott., belongs properly to May, but tardy individuals emerge till 

 the middle of June. 



b. In the other of the two principal types mentioned the period of 

 emergence for each brood is very long and entire families complete 

 their development successively at different periods, though belonging 

 to one brood only (" graduated emergence"); in this case there can 

 be distinguished " precocious families " and " tardy families " ; the 



