68 THE entomologist's RECORD. 



first days of July, but, at this season, rarely fly, and are only seen 

 when the males carry them into the air in copula ; in September they 

 begin to fly, bearing on their wings all the marks of a long life, and 

 some live till the end of the month ; one may conclude from this that 

 they show a true and proper summer lethargy, after copulation, and 

 that they begin to lay their eggs when the herbaceous vegetation re- 

 commences to grow ; there exist therefore examples of longevity 

 produced by " aestivation " (imagines aestivantes) similar to those of 

 hibernation. 



The other cause of error, which in southern countries, like ours, 

 easily leads to deception in the valuation of the number of broods, 

 consists in the summer " pause," and in that of winter, which inter- 

 rupt the emergence of Lepidoptera. I have already noticed the summer 

 pause [quies (estiva) in vol. xlviii. of the Bull. Soc. Ent. Ital.., p. 179 ; 

 I note that it lasts in the northern part of Central Italy about 15 

 days, between the beginning of -July and the beginning of August, 

 and that in Florence it lasts precisely from the 20th of July to the 

 5th of August. It overtakes some species during the emergence of 

 the second brood and divides it into a group of precocious individuals 

 and into a group of tardy individuals ("bipartite brood"). In Florence 

 this happens to Resperia vuilvoides, Elw. and Edw., which, among 

 the species with two short broods, produces the second earlier than 

 the others which generally commence to emerge immediately after the 

 summer pause. On the Monte Conca, near Florence, at a height of 

 about 800 m. above the sea, a similar splitting of a brood has been 

 observed in Plebeius ligurica, Obth., race mira, Verity, described 

 and figured in vol. xlv. of the Bull. Soc. Ent. Ital., p. 231 ; the first 

 group was found from the last days of June to the middle of 

 July, the second at the beginning of August ; no other 

 broods of this species were found in this locality, but we may 

 consider that it has two broods in localities less cold than the 

 Monte Conca, which has a fauna of distinctly high altitude, not- 

 withstanding its low height, owing to its having a north aspect; in 

 the Val d' Em a, near Galluzzo (Florence), I have collected liyurica at 

 the end of May and in June, therefore it is almost certain that it 

 behaves like its relative F. idas, L., which has two broods in all 

 Tuscany and even at Boscolungo, m. 1300, emerges twice (in the first 

 ten days of July, and in the second decade of August). 



Polyoimnatus icarus, Eott., and Agriades thersites, (Cant.) Chap., 

 have, as we shall see later on, two broods of long duration, consisting 

 of a series of families ; these last emerge successively, during nearly all 

 the good season, and there is no interval between the first and second 

 brood, which can only be distinguished by the appearance of the insects ; 

 the summer pause separates, also in this case, the earlier families of 

 the second brood from the rest, and they would doubtless be referred 

 to the first brood if their appearance didn't enlighten us. 



The winter pause has the same effect as the summer, and only 

 differs from it by its greater length : it overtakes the last brood of some 

 species soon after the beginning of the emergence of the perfect insects 

 and, interrupting it, converts the remainder into the first brood of the 

 following year; it is important to emphasize this fact, and to observe 

 that this subdivision of a single brood into an autumn and a vernal 

 group does not at all increase the number of generations or true broods ; 



