232 BKITISH BUTTEKFLIES. 



The wings beneath pale and shaded with grey, ornamented with a white line 

 and reddish-yellow spots — Bithys tyrrhenas (erix, Cram., 82, B). B. cnbentus, 

 Cram., 337, F-G. B. cethegus, St oil., 38, 5, 5, E. B. vesulus, Cram., 340, J-K. 

 B. sicheus, Cram., 144, C-D. B. lydus (eryx, Cram., 143, D). B. tephraeus. B. 

 leucophaeus, Hiibn., Zutr., 87-88. B. sphinx, Fab., Syst. Pap., 329 (dindymus, 

 Cram., 46, F-G). B. strephon, Fab., Syst. Pap., 344 (cyllarus, Cram., 27, C-D). 

 B. quereus, Linn., Syst. Pap., '122 ; Hiibn., Pap., 369, 370, 368. 



In 1835, Stephens used (Illus., iv., app. p. 404) the generic name 

 only for querciis, thus making this the type. In 1850, he uses (List, 

 p. 16) it in the same manner, whilst, in 1858, Kirby, in his little List 

 Brit. Rhop., also uses it for quereus. In 1869, Butler goes back on 

 this, and uses the name for strephon, Fab., cyllarus, Cram., agrippa,¥&h., 

 and dindymus, Cram. In 1875, Scudder notes (Hist. Sketch of Genera, 

 p. 127) that " the usage of Stephens and Kirby is indefensible, as 

 quereus must belong to Aurotis," but we have already shown that 

 Leach himself made betulae the type of Aurotis and Zephyrus, and 

 that both fall before Thecla and Buralis (with the same type). In 

 suggesting, therefore, "strephon" as the type of Bithys, he is much 

 too late, and his action altogether ultra vires. Scudder's note (op. cit.) 

 on Aurotis is equally illogical. He rightly points out that, in 1816, 

 Dalman founded this as a subgenus of Zephyrus for quereus, betulae 

 (type), pruni, w-album, and ilicis, and that Dalman names betulae as 

 type. He then says that " the last three of Dalman's species (supra) 

 belonging to Thecla, after the foundation of Zephyrus, quereus must be 

 taken as the type of Aurotis, if it is generically distinct from betulae, if 

 not, Aurotis falls," i.e., Dalman having made betulae the type of the 

 subgenus Aurotis and the genus Zephyrus, Scudder, 60 years after, says 

 that quereus and not betulae is the type of Aurotis, because pruni, 

 w-album, and ilicis belong to Thecla, which to us is, to say the least, a 

 remarkable conclusion. 



The Bithynid species are very characteristic and somewhat easily 

 recognised as such, and one supposes that they are capable of subdivision 

 into various natural groups. We find ourselves unable to deal with, or 

 to follow, the material as at present arranged in the British Museum 

 collection, and feel satisfied that some confusion occurs in the 

 " orientalis " section, especially among the females. A revision of the 

 entire group is altogether outside the scope of this work, although 

 undoubtedly needed, and a few general remarks on some of the 

 more characteristic species is all that is possible. The general 

 characters of the sexes are well exhibited in Bithys querciis, the males 

 being almost uniformly metallic in tint on the upper surface, chiefly 

 purple or green, the females with a brighter metallic blotch towards the 

 base, in the discoidal cell and the interneural space below, with usually 

 two (or three) pale spots outside the cell. This sexual colour dimorphism 

 in the Bithynids is most interesting, and, certainly, one of the most 

 striking features is the appearance of the two pale spots (orange or 

 white) just noticed. These produce a peculiar appearance, which we 

 may well call the "bdlus" type, as European collectors know the 

 marks as a rare form of aberration =ab. bcllus, Gerh., in female 

 />'. quereus. It also occurs as a rare aberration in ta.vila, Brem., but 

 becomes normal in ieana, Moore, dohertyi, de Nicev., pavo, de Nicev., 

 atasus S~ , Hew. (-\-katura $ , Hew.). In tsangkie, Obth., they are 

 united. In other species the metallic patch at the base of the wing 

 disappears, and the spots, separate (heeale, Leech) or united (duma, 



