302 



? . Papilio idas, Linnaeus, Faun. Suec. p. 284 (1761). 



Lxjcana argus, Lang, Butt. Eur. p. 105 (1884) ; Pryer, Rhop. Nihon. p. 18, pi. v. 

 figs. 1 «, 1 1 c (1886) . 



" Expands 1 to I'lO inch. The male is dark blue, nearly the same colour as L. cegon, which it 

 altogether greatly resembles ; the hind marginal border, however, is narrower and more 

 defined, the hind marginal spots of the hind wings are more distinct, and the white marginal 

 fringes are very narrow — not broad, as in mjon. The female on the upper surface almost 

 entirely resembles the female of L. ergon, but the orange hind marginal spots are rather 

 more distinct. Underside : ground-colour uniform brownish grey in both sexes ; the central 

 row of spots on the fore wings is more even, the last spot but one from the inner margin 

 being more in a line with the rest, and not, as it were, thrust inwards, as in L. agon ; the 

 silvery spots on the hind margin are much more distinct than in cvgon. The anterior tibia3 

 are not provided with spines." (Lang, I. c.) 



Dr. Lang, quoting Guenee, says that the larva is dark green, with a red 

 dorsal line and an oblique reddish streak bordered with whitish on each 

 segment. Food-plants Gemsfa, Melilotus, &c. 



The usual form of this species met with in Japan and Corea is brilliantly- 

 tinged with purple. It occurs in the mountainous districts of Central Japan, 

 and I liave received specimens from the Island of Kiushiu. The form 

 described below as var. insularis has so far only been found in Yesso, and 

 appears to be the only representative of L. argus in that i-sland. 



Var. insularis, var. nov. (Plate XXXI. figs. 5 $ , 8 c? •) Male. Ground-colour pale silvery 

 blue ; the nouration is wliitish except on the marginal area, where it becomes blackish ; outer 

 border of primaries broadly black. Secondaries have a well-defined series of submarginal 

 spots followed by a narrow black marginal lino. Fringes snow-white. 



Female. Black, much suffused witli blue-grey about the disc of tlic primaries ; discoidal spot 

 dibtant and l)ordercd with white ; there is a marginal line of almost confluent largo black 

 Bpots preceded by a brownish band. Secondaries have a series of elongate black spots, 

 intersected by a series of brownish lunules and bordered externally with \mvo white. Fringes 

 greyish tinged with brown. 



Under Hurfaco of both hcxc.h as in the type, l)ut paler; the female being as pale as typical males 

 and more suffused with blue at tho base. The silver spots are in some cases absent. 



Tliis form of L. nrgvn is easily distinguished from L. ihimenus l)y tho character of black marginal 

 borders to all the wings, the different colour of the neuration, and on tho under surface by tho 

 paler coloration, fulvous markings on the outer margin of primaries, and larger size of those 

 markings on secondaries. 



Kxi)an8e 'M-\W millim. 



A long s(;rios of this interesting form was taken by my native collectors in 

 the iieiglil)our)ioo(l of Hakodate in the Island of Yesso in June and July. 

 Lijcana nrfju.'i mik! Jj. mgon arc both exceedingly variable insects, and it is 



