252 LEPIDOPTERA. 



moor, which have the spots black and fairly distinct, and in 

 some cases distinctly white-centred, but the rings round them 

 are of a dusky dark yellow, very far from as distinct as on 

 the under side, yet forming an intermediate stage ; and in 

 Pembrokeshire, where the species is abundant, specimens are 

 found almost equally well marked, except that the white 

 centre of the spots seems, there, to be usually absent. That 

 district has also produced examples showing the curious un- 

 symmetrical white shading already noticed in E. Janira, in 

 one specimen in the right fore wing, in another in both hind 

 wings ; and also one having the whole upper surface of a 

 smoky grey, the under being also unusually pale. But the 

 most striking variation to which this species is liable occurs 

 in the spots of the under side, and takes two directions. One 

 is to a gradual diminution of the spots, in some cases all 

 being present and complete, with the yellow wings and white 

 pupils, but extremely small ; sometimes a few only are thus 

 present, in other cases the black and yellow rings have dis- 

 appeared and the white pujiils alone remain as white dots on 

 the otherwise plain under surface, and in rare cases every 

 vestige of a spot or dot has disappeared. All these gradations 

 of diminished and disappearing spots are included in what is 

 called the variety Arctc, but apparently the name was in- 

 tended to apply to those which have simply white dots. The 

 type of this variety in the British Museum is thus, with the 

 exception of one regularly ringed spot op the hind wings. 

 The other range of variation in these spots is to a series of 

 very large and altered spots, most of them ovate or irregularly 

 elongated, the central white dot enlarged and lengthened, as 

 well as its black and yellow rings. Mr. Herbert Goss has 

 some, taken, I believe, in the New Forest, in which the white 

 pupils have become mere white streaks from this extreme 

 elongation. In other cases there is, with the change of shape, 

 a great enlargement of the yellow ring. These are connected, 

 by imperceptible gradations, with the ordinary forms, and in 

 the collection of Mr. C. A. Briggs may be seen a series show- 



