NISONIADES TAGES. 268 



a row of small white dots on outer margin ; a wavy transverse row of 

 pale spots parallel with the outer margin, sometimes well-developed, 

 at other times nearly obsolete; fringes of the same tint as the hind- 

 wings, tipped externally with grey. 



Sexual dimorphism. — The sexual dimorphism of this species is 

 most marked. Not only has the $ a strongly-developed costal fold, 

 filled with very specialised androconia, the $ being without this structu- 

 ral peculiarity, but the colour and markings usually show distinct sexual 

 characteristics. The $ costal fold of this species has already been 

 described (antea, p. 261). The special androconial scales of this species 

 are quite fine, like hairs, 0-45mm.-O5mm. in length, 00045mm. wide, 

 blunt, with a golden gloss ; they have rough uneven edges, and are 

 distinctly hollow inside (Aurivillius). 



Variation. — This species exhibits a considerable amount of minor 

 variation, nor is this in any wise confined to a difference between the 

 specimens of the first and second broods, although the second brood 

 examples from southern Europe appear to be of a much deeper brown 

 hue than any others examined. The spring specimens appear to be, 

 on the whole, somewhat larger than the summer ones, although 

 many exceptions occur. The spring examples vary, however, 

 considerably in the ground colour, some being rather pale drab- 

 brown, others deep fuscous-blackish, whilst the transverse bands 

 show every intermediate stage between solidly united longitudinal 

 lineolae, stretching for some distance across the wing, to almost 

 absolute obsolescence. The most striking variation, however, is 

 to be seen in the median area, the space between the two 

 dark transverse bands being sometimes wholly filled up with grey 

 (white) scales, frequently extending into the outer and basal areas, 

 giving the appearance of alternate dark and pale transverse bands. 

 The marginal row of dots, too, varies greatly in intensity, being some- 

 times very clearly marked, at other times more or less obsolescent, 

 whilst the three little characteristic costal dots may be reduced to one 

 or even none, or continued faintly through the outer transverse band. 

 The hindwings have a similarly variable outer marginal row of white 

 dots, and a faint indication of a central band of pale spots, which 

 suggests, in the best marked examples, an analogy with the transverse 

 band of Hesjoeria malvae. The undersides of British (and European) 

 examples vary scarcely at all ; they are of an almost unicolorous brown 

 colour (sometimes somewhat brighter, at others duller), and, as the 

 insect sits with its wings deflexed, and not with its undersides 

 exhibited, it will be seen that there is no need for pattern (or varia- 

 tion) on the undersurface. An exception, however, occurs in the eastern 

 race, var. sinina, in which a row of pale (whitish) spots traverses the 

 underside, and forms a conspicuous character. Of the more or less 

 casual references to the variation of this species, we note that Kane 

 says that, in Galway and Fermanagh, the specimens have very distinct 

 grey markings on the forewings. Raynor observes that, in the Haze- 

 leigh district, where the species is abundant, it varies a good deal in 

 the coloration of the forewings, one example having the forewings of 

 a deep brown-black, with all the pale markings suppressed, except the 

 series of white spots along the outer margin. Miss Fountaine says 

 that the eastern Europe and Asia Minor examples seem somewhat 

 darker, and less varied in pattern. Haberhauer notes that, in the 



