CYANIRTS SEMIARGUS. 26& 



confounded with its allies, L. cyllarus or L. acis. The 3 is of a violaceous-blue 

 above, and of a mouse-grey beneath, tinted with iris-blue at the base of the hind- 

 wings. The 2 is entirely black above, with the fringe white, without the iris- 

 blue that characterises the underside of the hindwings of the 3 . This insect does 

 not appear to be rare in July, below St. Martin, on the banks of the principal 

 affluent of the Vesubie, the Borreon. It is probable that the insect may be found 

 in other elevated places in the Alps of our department. A few weeks before my 

 arrival at St. Martin, the species had already been discovered by Mr. Rod. Zeller, 

 who at first did not recognise it (Milliere). 



The coelestina of the Alpes-Maritimes, as figured by Milliere, is. 

 without doubt semiargus of a deep violet-blue, with a well-defined, 

 black marginal border and discoidal lunules. The underside is, indeed, 

 quite typical, except that the forewings have five well-marked, white- 

 ringed, dots and the double one (very small and obsolete),, 

 and six well-marked ones, with again the double one small, on 

 the hindwings, the discoidal on the underside of fore- and hindwings 

 well-marked, but fine ; the bases of the hindwing blue. It appears to 

 agree very well indeed with specimens from Bergiin, Ticino, Cour- 

 mayeur, etc., in our collection. Indeed, one suspects it to be just the 

 ordinary form of the hot southern valleys of the Alps of Central 

 Europe and southern France, although some of those from the lower 

 alpine valleys of those parts of Savoy and the Hautes-Alpes abutting 

 on the lowlands of France, are narrow-bordered and more like the var. 

 cimon, Lewin. 



y. var. montana, Mever-Diir, " Schmett. Schweiz," p. 90 (1851) ; Frey, " Lep. 

 Schweiz," p. 21 (1880); Lang, " Butts. Eur.," p. 130 (1884); Kane, " Eur. Butts.," p.. 

 50 (1885); Ruhl, " Pal. Gross .-Schmett.," pp. 298, 767 (1895); Tutt, " Brit. Butts.," p. 

 164(1896); Staud., " Cat.," 3rd ed., p. 89 (1901); Wheeler, " Ent. Rec," xiii. pp. 

 120-121 (1901); "Butts. Switz.," p. 25 (1903) ; " Ent. Rec," xvii., p. 199 (1905).— 

 With the increase of elevation, on the other hand, acis becomes smaller ; even in 

 the mountain- region in the meadows around Meiringen (2500ft. above sea-level) it 

 flies about June 13th-15th in countless numbers, in general not larger than optilete ; 

 at considerable heights of 4000ft. to 5000ft. above sea-level, in the subalpine region, 

 e.g., in the (Eschinenthal, the forewings of this small form assume a narrower, more 

 pointed, form (mid-July), until at last, in the still higher alpine region, at 6400ft., as 

 at Schwarrenbach on the Gemmi, the butterfly, August 11th, attains only the size of 

 aegon. This var. montana differs also somewhat on the underside in two directions. 

 The greyish tone runs more into brownish and the eye-spots are larger and more 

 sharply bordered with white. In the anal angle of the hindwings in a male from 

 the Grimsel faint traces of darker marginal lunules appear. This example, as well 

 as those from Schwarrenbach, agrees in shape, size and arrangement of eye-spots on 

 the underside so exactly with a butterfly taken by Frivaldsky, in the Balkans, and 

 sent to me as Pap. bellis, that I observe no other difference than that in this Pap. 

 bellis those traces of darker marginal lunules on the underside of the hindwings 

 have developed into reddish-yellow spots. Freyer figures (Neu. Beit., v., pi. 398, 

 fig. 12) this bellis in both sexes; though the male is, according to my specimen, 

 much too large, the forewings too rounded, the blue ground colour much too bright, 

 and the black border too narrow. In respect of the brownish marginal lunules of 

 the underside, he says, that they are not visible in every example. In this case, 

 therefore, the questionable P. bellis may turn out to be nothing more than a 

 southern modification of our var. montana of acis. P. acis (Freyer, Neu. Beit., pi. 

 451, fig. 4) is good and represents one of the low level region (Meyer-Dur). 



The var. montana, as a race, is a doubtful quantity, and Meyer-Diir's 

 general statement that "the higher the habitat, the smaller the 

 butterfly," must be accepted with caution. It may be true that, com- 

 pared with the largest examples of the plains of Central Europe, often 

 measuring 32mm. -35mm., those of the mountains generally are 

 smaller, though, in the Laquinthal and various parts of Ticino, up to 

 5000 ft., the specimens often measure 30mm., and an example from 



