118 BRITISH BUTTERFLIES. 



far from the outer margin ; it starts from the upper, but does not 

 extend to the lower, margin, terminating in the middle of the fore- 

 wings. This spot is visible both on the upper- and undersides, but is 

 rather less distinct beneath. This butterfly has no black comma, like 

 the male of P. thaumas, but it more resembles the female of the latter.* 

 I have never taken this insect myself, but I lately received two 

 specimens from a friend from Landsberg-on-the-Warthe. As this 

 species is never found in our neighbourhood, although P. thaumas is 

 found here every year in abundance, and the above described differences 

 are found in all the specimens of this species which I have seen in the 

 possession of my friend, it seems to me probable that this butterfly is 

 a distinct species, and not a mere aberration of P. thaumas (Yon 

 Eottemburg, Der Naturforscher, vi., pp. 30-31). 



Imago.— 22mm. -27mm. All four wings orange-brown tinged with 

 fulvous, and irrorated with dark fuscous ; on forewings, an elongate, 

 longitudinal blotch of paler orange in the discal cell, a transverse, 

 similarly coloured crescentic series of pale spots forming the 

 angulated line, just outside the cell; $ with a well-marked andro- 

 conial streak ; traces of a row of paler dots sometimes parallel to hind 

 margin of hindwings ; the margins of all the wings narrowly black ; 

 nervures indistinct ; fringes yellowish-grey. The undersides almost 

 uniform greenish-grey to orange-yellow, the inner margin of forewings 

 blackish, and the apex yellowish. 



Sexual dimorphism. — The sexual dimorphism in this species is 

 most marked, the $ possessing a well-developed androconial pocket, 

 passing obliquely beneath the median nervure of forewing towards the 

 inner margin, much resembling that of A. flava : the pale longi- 

 tudinal discal spot, the crescentic series of pale spots (forming upper 

 portion of the angulated line), and the transverse band of pale 

 spots crossing the centre of the hindwing is much less distinctly marked 

 (often absent) in the $ than the ? (although the latter sex varies greatly 

 in this respect). The ? appears to be, on the whole, a larger and more 

 heavily built insect than the J . 



Gynandromorphis.m. — The following is the only gynandromorphic 

 example we can trace : 



Left side $ , right side ? . Captured at Swanage, July 16th, 1903 (Ford, Kut., 

 xxxvi., p. 242). 



Variation. — The species is distinctly not a variable one, although, 

 as already noted, some variation occurs both on the undersides and 

 uppersides of the wings. In the former, some are much greyer in 

 tone, others more orange, the former inclining to greenish-grey, the 

 latter to orange-yellow, and whilst the former have a fairly well- 

 developed, bright, inner marginal patch on the hindwings, in the more 

 brightly tinted ones this is lost in the ground-colour. On the upper- 

 side, the variation chiefly consists in the depth of the 1 ground-colour, 

 some having an excess of dark fuscous, and hence becoming darker than 

 usual, others more orange or golden-brow n m their tint, and hence being 

 brighter in hue, whilst extreme British S s are very dark and tinged with 

 green ah. n'rcscais, n. ab. There is also, in both sexes, considerable 

 variation in the conspicuousness (or otherwise 1 ) of the pale markings, 

 whilst in some examples there are well -developed traces of pale 



* Evidently it is the Female that Von Rottemburg dc-cribes. 



