CELASTKINA ARGIOLUS. 391 



short, thick, with very numerous short flat spines nearly throughout 

 its length. The clasp of C. oreas, Leech, is different, and one suspects 

 that nebulosa, Leech, goes with the latter." As supporting the above 

 view, Bethune-Baker writes (in litt.) : " I have carefully compared 

 the male genitalia of argiolus, huegelii and pseud argiolus, and am very 

 doubtful if it would be possible to separate the species on these 

 characters ; there are slight points of difference between the first and 

 second, but these appear to be due to the relative sizes of the two 

 insects, huegelii being very much larger than argiolus ; Japanese 

 (ladonides) and American (pseudargiolus) examples have male genitalia 

 exactly like those of our European specimens." Bethune-Baker 

 also notes that, "one w T ould, however, find no difficulty in separating 

 the coelestina, huegelii and argiolus forms from one another, both by 

 the appearance of the upper- and undersides," and adds that "all the 

 eastern forms are entirely without the blue gloss on the underside, 

 whilst Asia Minor specimens generally also lack this." On the strength 

 of this very definite evidence, we have to admit the eastern and American 

 (yseudargiolus) insects as mere geographical races of C. argiolus. 

 Among the items in which variation may be noted in our European 

 (and British) examples, are (1) the intensity and shade of the ground 

 colour ; (2) the width of the black marginal border (especially in the 

 female), where it sometimes extends over the greater part of the wing ; 

 (3) the size ; (4) the greater or less development of the black dots on the 

 underside, including the marginal lunules. Besides the two different tints 

 of blue — lilac or azure-blue and warm mauve — usually found in ourBritish 

 examples ( $ ), various aberrational colour-forms have been noted. Thus, 

 Battley exhibited (Ent. Eec, iii., p. 270), at a meeting of the City of 

 London Ent. Soc, November 3rd, 1892, two males of a colour 

 approaching that of Agriades bellargus, and Dennis is reported (op. cit., 

 viii., p. 149) to have exhibited at the South London Ent. Soc, 

 June 25th, 1896, some very brilliant specimens from Horsley, also of 

 a shade approaching A. bellargus. Sabine records (Ent., xxxiii., p. 303) 

 a pale lavender-coloured male, captured at Erith, in 1900, also three 

 or four exceptionally dark males, another male having some of the 

 colouring pigment absent on the right forewing ; whilst yet another 

 male is reported (Ent. Rec, viii., p. 150) as having the left wings of 

 a deep silvery greenish-blue colour, rather like that of A . corydon, the right 

 wings normally coloured. Burrows notes that, in Clark's coll., there is a 

 male with the right side of the normal violet- blue coloration, the left side 

 being blue-green almost metallic, a tint usually recognised as distinctly 

 female in character, but this example shows no sign of gynandromorphism; 

 in the same coll., a large female from Epping Forest, May 5th, 1896, has 

 the left forewing streaked longitudinally with yellowish -white. The 

 detailed account of the variation of Celastrina pseudargiolus, by Edwards 

 and Scudder, has led to a considerable amount of observation being 

 paid to our European species, C. argiolus. The marked sexual varia- 

 tion of the species is accompanied by a more or less distinct seasonal 

 variation, particularly in the females. As to this form of female 

 variation, we have already noted (Brit. Butts., p. 188) that "the width 

 of the band on the forewings varies much, sometimes extending more 

 than halfway between the apex and the thorax, and being sufficiently 

 broad to unite with the discoidal spot ; at other times it is not more 

 than half this width. In some specimens, too, it scarcely reaches the 



