RURALIDI. 



227 



clearly indicated. The imagines are, on the whole, considerably 

 larger than those of the Strymonids ; the hindwings are usually 

 furnished with one short caudal appendage, and a slight extension of 

 the anal angle ; there are no denned androconia observable, but the 

 sexual dimorphism in colour, marking, and to a less extent in shape, 

 is very distinctly marked. The neuration of the forewings is 

 characterised by the upper discoidal nervule of the forewing being 

 given off from the subcostal nervure some distance beyond, instead of 

 a little before, or at the apex of the discoidal cell, and similar in the 

 two sexes. The underside markings of the Bithynid species are 

 somewhat nearer those of the Strymonids than are those of the 

 Ruralids, of which the group represented by it. betidae has its most 

 divergent form in saepestriata. 



Both groups have representatives without a caudal appendage to 

 the hindwings ; in the Bithynids, khasia, de Nicev., in the Ruralids, 

 raphaelis, Obth., with its var. jiamen, Leech. Of the difference in the 

 sexual coloration, readily recognised in the two groups by that of 

 B. querciis and R. betulae respectively, much might be noted, and of 

 it de Niceville writes (Butts, of India, iii., p. 300) : "The species are 

 very variable in colouring, the male of R. betidae brown above, with 

 some pale ochreous markings on the disc of the forewing on the 

 upperside, the female with a prominent orange band, the underside 

 also orange, much brighter in the female than in the male; B. querciis 

 is purple on the upperside of both sexes, but the colour is much 

 restricted (though more intense) in the forewing, and replaced by 

 blackish in the hindwing, of the female. The Indian species (which 

 all belong to the Bithynid section) are all more or less green, blue, or 

 violet (in one species) on the upper surface of the male, this colour 

 being most magnificently metallic in several of the species, less so in 

 others. The females differ widely, as a rule, from their respective 

 maJes, and, in Japan, according to Leech (Proc. Zool. Soc. Lond., 

 1887, p. 412), one species, japonica, Murr., has four distinct female 

 forms, besides which all intermediates occur." This statement 

 must be accepted with caution. Noting some of the Indian species, 

 he remarks that "the female of dumq, Hew., is black above, with 

 an orange band on the disc of the forewing ; that of syld, Koll., 

 is more or less blue ; of birupa, Moore, blackish, with two pale 

 patches on the forewing ; of icana, Moore, and dohertyi, de Nicev., the 

 females are very like that sex of duma, but have a little purplish 



towards the base of the forewing The opposite sexes of 



ziha, Hew., are marked and coloured exactly alike, the upperside of 

 all the wings blue, the obliquely-placed spots on the forewings white." 



The Ruralid [sens, strict.) egg is more Lycsenid in its general 

 appearance than the Strymonid, being somewhat less flattened, i.e., 

 fuller, but like the latter passes the winter, the young larva being 

 fully-formed within the eggshell for a considerable time before 

 hatching takes place. The eggs of our European species are laid on 

 the twigs of their foodplants, those of Bitkys querciis on twigs of oak, 

 and those of Ruralis betulae on twigs of blackthorn. Chapman, 

 speaking of the Ruraline egg (as exemplified by R. betidae), says: 

 In form, it comes very near Thecla tit us, as figured by Scudder, 

 but is not quite so flat ; the sculpturing is more elaborate. The 

 structure seems more allied to the pits of the Chrysophanid eggs, as 



