174 BRITISH BUTTERFLIES. 



of central Europe, or the lowlands of southern Scandinavia, no doubt 

 the form aegiades', those from the Alps are of deeper, more purplish, 

 blue, often approaching the lilacine form, the dark margins of all the 

 wings well-developed, the dark shading prolonged interiorly along the 

 nervures in the form of rays, the discoidal lnnules generally distinct 

 on the upperside of all the wings, whilst, on the underside, they are 

 rather grey, or even grey-brown, than whitish- or bluish-grey ; and 

 they are usually distinctly smaller. These are of the philonowus 

 form. Of these differences Reverdin notes (in litt.) that, on placing 

 $ s of the " alpine " and " plain " races side by side, the brighter tint 

 of the latter is apparent, whilst the former are usually smaller, and 

 the black margins wider and more diffuse. In the British Museum 

 collection, well-defined examples of the bright " plain " form are 

 labelled " Odalen," " Kreuznach," " Rennes," " Bourg d'Oisans," 

 " Tyrol " (evidently a valley specimen), " Zurich," etc. Hormuzaki 

 notes (Soc. Ent., viii., p. 18) that the<? s of this species are particularly 

 fine throughout the Bucovina, but near Czernowitz are especially so, 

 being fully 30mm. in expanse ; the brownish-black border is very 

 broad, 3mm. -4mm., on the inner edge gradually blending with the 

 ground colour, the white fringes also being extremely broad. The 

 Bulgarian examples in the British Museum coll., are also of good size, 

 with well-developed marginal border in the J s, and noticeable 

 discoidal spots. As illustrating the change that occurs as a matter of 

 altitude in the same district, one may note that the $ s from Bourg 

 d'Oisans are markedly of the "plain" form, those from Oulx have a 

 well-marked marginal border, those from the Col du Lautaret a much 

 wider border and distinct discoidal spots, and markedly of the 

 "mountain " form. Zeller states (Stett. Ent. Ztg., 1872, p. 37) that 

 the $ s from Bergiin agree on the upperside with those from Posen, 

 even the nervures being scarcely darker ; Gillmer notes (in litt.) that 

 the S in Anhalt is small, dark blue in colour, with a fairly broad, 

 dark margin. A $ , in the British Museum coll., taken in 

 Portugal, June 8th, 1880, is of a blue-grey or slaty-grey colour, 

 with rather narrow marginal border, and very small discoidals 

 on forewings = ab. plumbeus, n. ab. The width of the marginal 

 border in the J varies exceedingly. As already noted, our own 

 British chalkhill race has hardly any marginal border to the fore- 

 wings, and its place is occupied on the hindwinga by marginal 

 dots. These dots on the hindwing are sometimes particularly well- 

 developed = ab. marginipvncta, n. ab. The variation in the width of 

 the marginal borders is noticeable in almost all the races, e.g., some of 

 the mountain forms have very wide borders, extending far along the 

 nervures towards the bases of the wings ; this is particularly so on 

 the southern slopes of the Alps at moderate elevations, e.g., Piotta, 

 Brugnasco, etc. They are also larger in size than the usual mountain 

 examples. Otherwise, they are of the general colour, appearance, etc., 

 of the philonomus form, and have been named killiasi, Christ. There are, 

 therefore, to be considered in almost every race, examples with narrow 

 marginal borders — ab. angmta-margvnata, n. ab. ; those with moderate 

 borders, e.g., up to one-fourth of the wing expanse -ah. intermedia-mar- 

 ginata, n. ab., and those with wide borders, e.g., more than one-fourth the 

 width of the wing ab. lata-marginata, n. ah. The examples from Ticino 

 are particularly-well-margined, and Blachier notes two .j s from Tstria, 



