AGRIADES CORIDON. 9 



noticed (supra). Apart from these, the general similarity of the 

 species in all parts of its range is very striking, although still subject 

 to considerable aberrational variation, and one obtains almost exactly 

 the same range of forms between Franzenshohe and Ferdinandshohe 

 on the Stelvio, at from 7500 to 9000ft. elevation, as at Gex in the Jura, 

 Mt. Saleve in Haute Savoie, Digne in the Basses-Alpes, Fontainebleau 

 Forest in Central France, Torre Pellice in Piedmont, Dover and Cuxton 

 in Kent, Guildford in Surrey, and Assisi in the Apennines, and any 

 attempt like that of Neustetter (Int. Ent. Zeit. Guben, iii.,p. 198) to set up 

 as racial the ordinary mountain specimens, shows a complete failure to 

 understand the real variation of the species. The colour variation of 

 the $ s, though wide, is not remarkable outside Spain and Asia Minor, 

 yet the shades of silvery-blue or silvery blue-green in the ground 

 colour, may be extreme, and extend from a pallid thinly-scaled whitish 

 form (ab. albescens, Ckll.), or a very well-scaled pale silvery-blue form 

 ( = apennin-a, Zell.), through almost every tint of silvery-blue until 

 it reaches a bright glossy silver-blue (hispana, H.-Sch.), approach- 

 ing, but in its most advanced examples (hispana ab. coelestis, n. ab.) 

 falling perhaps just short of, the tint of A.thetis, or silvery blue-green (ab. 

 riridescens, n. ab.); but the most blue $ s found in Britain and Central 

 Europe never reach the hispana standard of blue, however nearly they 

 may be sometimes said to approach it. Oberthur notes (Etudes, 

 xx., p. 21) a $ taken at Dover, 1878 (How T ard-Vaughan coll.), and 

 two $ s (Bellier coll.) of a pale grey colour, scarcely bluish, and w 7 ith 

 the upper edge of the marginal ocelli of the hindwing tinged with 

 fulvous =grisea-suavis, n. ab. The amount of modification of the dark 

 margin, brings in another item to be considered in its general colour- 

 scheme. There is, in addition, a distinct difference produced by the 

 variation in the quantity and length of the hair-scales, and the $ s that 

 are almost devoid of the latter (ab. glabrata, n. ab.) exhibit their sbiny 

 underscales, and present a remarkably characteristic appearance due 

 to the absence of the silky look that usually marks the species. Among 

 these smoother examples occurs a rare form with the ground colour 

 strongly suffused, resulting in a brownish-grey hue, due to the develop- 

 ment of a large number of small dark scales, but so thin is the scaling 

 compared with the normal, that the markings of the underside show 

 fairly distinctly through ( = ab. suffusa, Tutt). Hodgson notes (in litt.) 

 a brownish-drab $ taken in Surrey, and we have a more plumbeous 

 example from Jaca in the Spanish Pyrenees (ab. jdu albescens) a mere 

 modification apparently of the suffusa form. Beverdin notes the Savoy 

 and south-west Swiss examples as not very variable, sometimes 

 more shiny and more silky, at other times more dull, the Rivieran 

 race, he says (from Pardigon), being strikingly greyer and duller than 

 the Swiss and Savoy races ; whilst Blachier notes the colour of A. 

 coridon as more or less bright silvery-blue, sometimes very pale, some- 

 times very deep. The border varies very considerably, and may 

 consist of little more than a mere line (angustimargo, n. ab.), or 

 it may be developed into a deep black band 3mm. -4mm. (type) 

 in extent, or it may be grey, or brownish, or dark and ill- 

 defined inwards, or diffused into the ground colour at some distance 

 from the margin, sometimes extending over fully the outer third of 

 the wing, and sometimes further suffused along the costa as far as the 

 discoidal lunules ( = ab. marginata, Tutt); racially the most suffused 



