262 BRITISH BUTTERFLIES. 



varying degrees of spot -reduction ; it appears to be a general form of 

 aberration, but is particularly frequent in specimens from Norway and 

 Greece ; two very fine examples of antieo-obsoleta, of the var. helena, 

 the snbmedian row of spots absent on forewings, and almost normal 

 on hindwings, are very interesting. Between the discoidal lunule of 

 the hindwing and the base are a variable number of spots ; there is 

 generally one near the costa of the wing just before the base ; more 

 rarely a spot in the middle of the inner margin ; also, very occasionally, a 

 spot between the discoidal lunule and the base of the hindwings. In 

 the example of ab. lineata, in the British Museum coll., the 2nd of these 

 spots is united with the rare supernumerary spot 9 near the anal angle 

 into a long streak. The discoidal lunules of the hindwings are 

 always less marked than those of the forewings, and are sometimes 

 obsolescent. The relative position of spots 1, 2 and 3 on the underside 

 of the hindwing is interesting ; sometimes 1 and 2 are under each 

 other, at others 1, 2 and 3 are in a straight line ; this point is brought 

 out in some of the descriptions and figures of Bergstrasser's aberrations. 

 The absence of antemarginal spots on all the wings is one of the 

 main features of the typical form of this species ; in various degrees 

 of development these marginal spots may be traced, however, in in- 

 dividual specimens, in the earliest stages in faint grey, darkening, 

 however, in colour, assuming even finally the form of orange lunules 

 above the marginal spots, first near the anal angle of the hindwings, 

 and, lastly, throughout the length of the marginal series and extending 

 to the forewings, and all the spotting increasing in intensity until, in 

 var. persica, the full Plebeiid underside spotting is definitely assumed. 

 In the British Museum coll. the mode of development of these grey 

 antemarginal spots is well shown in several examples of both sexes ; 

 at first merely faint interneural pale lunular shades shutting off 

 centrally a piece of the ground colour, secondly the darkening of this 

 portion of ground colour, thus contrasting with the light margin, and 

 so on till a noticeable series of marginal spots can be traced ; this 

 development begins on the hindwings near the anal angle, and extends 

 only rarely to the forewings in the examples of the plain, becoming 

 commoner in Bosnia, Bulgaria and Greece, where the dark grey 

 kernels commence at the anal angle of the hindwings to take on a 

 definite orange form, and so leading up to the well-developed under- 

 side of var. persica. Becher (Ent.) states that the $ s at Carlsbad, 

 sometimes show faint traces of a row of spots along the hind margin 

 of the hindwings. Meyer-Dvir notices (Schmett. Schweiz, p. 90) that 

 in var. montana there are sometimes weak traces of dark lunules. 

 Blachier says (in litt.) that, in the examples in his collection, he finds 

 sometimes as many as five or six obscure grey spots on the margin of 

 the hindwing, whilst some of the grey spots are surmounted with 

 slightly-marked white spots (as in two <? s from Versoix and Mont 

 Saleve) ; sometimes, on the contrary, there is a series of white spots 

 between the grey spots and the fringe ($ from Martigny), whilst there 

 may be a white edging both above and below the grey spots ( $ from 

 Mont Saleve). Reverdin states (in litt.) that, in many specimens of 

 both sexes in his collection, there are faint indications of marginal 

 spots, but that these are sometimes more marked and quite visible to 

 the naked eye (eleven S s and four $ s), and these interneural spots appear 

 as almost rounded, those nearest the anal angle more distinct, some- 



