SEASONAL VAIilATIoNS OF PARARGK MEGEHA. 211 



the case of Ruwicia phlacax, L., which I have dealt with in the I'Utt. 

 Bee, xxxii., p. 7. 



Having thus cast a glance on the variations of nieiiira in a general 

 way, let us see w^hat races are detectable and what features their 

 generations exhibit. 1 find that in the case of this species, as in those 

 of others described by me in this Journal, the most natural, and, at the 

 same time, the most practical, classification consists in following the 

 main line of variation I have described above, as afforded by the features 

 of the underside of the wings, and in dividing it conveniently in the 

 number of grades suggested by the races and generations, as they fall 

 into groups. Here, however, it must be noted that other characteristics 

 associate with the fundamental ones and create four parallel lines of 

 variation ; these run through the various grades, so that each of the 

 latter consists in various forms, most of which are characteristic of a 

 race and a generation. I will endeavour to show this clearly in a 

 tabubir form at the end of this paper. 



Grade I: Linueus gives " Austria and Denmark " as the habitats 

 of the species, so that the nymotypical race is the one which spre^ids, 

 as far as I can ascert-ain, to the whole of Northern and Central Europe, 

 We shall see that F. J. Ball has described and named the second 

 generation of Central Europe, thus restricting the Linnean name to 

 the first. The latter can be described as the darkest amongst the 

 usual forms of the species, on account of the extent of the pattern on 

 both surfaces ; the fulvous colour is paler, more yellowish and duller 

 than in the other grades ; the underside of hindwings is distinctly 

 yellowish. The upperside markings seem to vary in extent according 

 to localities. All the German authors mention particularly niediolufieiis, 

 Fuchs, Jhrb. Nassau, 1892, p. 87, from Nassau on the Middle Rhine, 

 and Seitz says it is predominant at Bergstrasse in some places; it thus 

 is quite a local race. It is described as having all the pattern of the 

 upperside increased in extent and especially the androconial band of 

 the male one-third broader than usual and the transverse streak of the 

 forewing in the female also much broader. If the underside of the 

 hindwing is darker too, this would constitute a grade standing before 

 this one, of nymotypical )iief/era but I find no record of the aspect of 

 that surface, so that I take it to be purely a variation of the upperside ; 

 this is far more likely, on account of ii:s much greater variability. 

 The form standing opposite to the last described, by a strong reduction 

 in the extent of the upperside markings, so that those of the forewing 

 are in the female as thin as they usually are on the underside, is 

 alticnla, Vrty. {Bull. Soc. Eiit. ItaL, xhi., p. 269, 1911). I described 

 it from specimens collected by myself at the Baths of Valdieri, m. 1375, 

 in the Maritime Alps, as the mountain race of nie/iera. This, I fear, 

 is not correct : alticola is found as an extreme individual form in most 

 races, and especially in particularly hot and dry localities, l)ut it seems 

 to be the result of any sort of unsuitable condition which the 

 individual has undergone. As altitude is, apparently, the chief 

 hindrance to the development of this otherwise nearly ubiquitous 

 species, it is very likely alticola is more frequent at the highest 

 altitudes it reaches, according to regions, but I have found no evidence 

 that it is prevalent anywhere. 



Race iNFRAPALLENs, mihl : As I have already mentioned, the African 



