THE VAKIOUS MODES OF EMEKGENOE. 



107 



third from the first and second. We are obliged, on the contrary, to 

 conclude that the greater number of families, or of individuals, are 

 reproduced once a year only, as happens to the entire species in less 

 southern countries, and that even with us it is only the minority which 

 profits by the more favourable climatic conditions to reproduce itself 

 two or three times. We are concerned, therefore, with a species which 

 belongs only partially to the type of emergence with three broods ; 

 examples so conspicuous and so constant in all regions are not 

 numerous, but there exist also with us, some others which constitute a 

 transition from one type to the other. 



Thus, Nisoniades taijes, Antiiadea sylvanus, and ScoUtantides baton are 

 of the "bigenerate" type, but the second generation is so limited, both 

 in the amount of individuals and in duration, that those species can 

 practically be considered of the " annual " type ; the first generation 

 instead is extremely long, and in the case of baton individuals of the 

 two broods emerge together in August, those of the second being 

 distinguished by their very small size. We then also have the genus 

 Cupidn, and especially sebrns, which belong to the " bigenerate," but their 

 second brood is so small and variable, that they ought almost to be 

 grouped with the "annual" species; the reduced broods are called 

 " partial," We have also a third graduation in some species which 

 undoubtedly belong to this last group, but which in special geographical 

 and annual conditions, produce a second brood; for example, there has 

 been several times noted an emergence of EucJiloe crdt^neri, Btl., at the 

 beginning of September,* which constitutes, perJaaps, a second brood 

 (it seems, however, more probable that it is only a case of the emergence 

 of tardy individuals of the first, that is, of an apparent brood ; this 

 hypothesis is confirmed by the fact that the nymphosis of crauieri can 

 also be " biennial") ; Querci has collected at Formia (Caserta) during 

 an exceptionally mild and dry October, a series of very small Angiades 

 sylvaniis, which Turati has named sylvanellus, whereas, generally, there 

 exists also in that locality one brood only from May to July, or 

 possibly a second partial one in September. At the end of August, 

 1917, I collected a small numoer of individuals of the two sexes of 

 Melitaea athalia, Eott., at Forte dei Marmi, where the species is 

 abundant in June. In this category there would also be the real 

 autumnal broods of some species, of which we must, perhaps, admit 

 the exceptional appearance in favourable years, and which must not be 

 confused with the much more frequent apparent broods (see p. 69). 

 These appearances at unusual periods might be called extraordinary 

 broods, in contrast with the ordinary broods. 



Returning to the consideration of the ordinary broods, according to 

 their importance, there does not seem to be any connection between 

 the number of individuals and the degree of robustness of their 

 structure ; thus, Melitaea phoebe, Kn., is an eminently summer species, 

 whose first brood is very secondary compared with the other in all 

 regions, and, notwithstanding, it is composed of individuals much 

 larger and more brilliantly coloured, precisely as in M. didyma, where 

 the first brood is, on the contrary, very far the primary. 



* Stefanelli captured a couple at Fiesole, in 1886 ; I possess a male collected at 

 Signa. I have myself collected four individuals, on September 4th, 1913, at the 

 Badia a Coltihuono, in Chianti. The two forms of the species have representatives 

 among them.— R.V. 



