230 BEITISH BUTTERFLIES. 



is the marked sexual colour dimorphism that occurs in the group. 

 The general appearance presented by the sexes of Bithys quercus may 

 be taken as characteristic of the Bithynid section, but one can hardly 

 say that the parallel characteristics of the Euralid section are equally 

 well shown by the sexual difference exhibited by Ruralis betulae, for 

 few, if any, of the species have so much dark brown as has this in the 

 $ , although the tendency to develop more orange, at the expense of the 

 brown, is throughout more marked in the female than in the male. 

 One of the most striking features of the females of the Bithynid group, 

 is the development of two (or three) pale (orange or whitish) spots just 

 beyond the discal cell, forming what one may call the " bell us " type. 

 This feature is characteristic of the Bithynid female throughout, and 

 the study of its modifications leads one to suspect it to be a very 

 ancestral marking of the species of this group. 



Gynandromorphism appears to be a very rare phenomenon among 

 the " hairstreaks." Among the Buralines we are able to record the 

 following : 



1. Bithys taxila, Riihl, "Pal. Gross-Schmett.," i„ p. 321 (1893).— Left ?, 

 right <? . Found near Nikolajewsk. 



2. Bithys quercus, Junkel, "Iris," xviii., p. 26, pi. i., fig. 6 (1905). — Ground 

 colour of S , with dark hindmarginal band of <? , in addition ? purple patch on 

 right forewing. Bred from larva taken near Lauterbach. 



3. Bithys quercus, " Ent.," xxxiii., p. 157. — Right c? , left ? . 



4. Ruralis betulae, Wiskott, " Iris," pi. x., fig. 4, pp. 379-80 (1897).— Right s , 

 left ? . Bred at Hamburg. 



5. Ruralis betulae. — Left side <J , right side ? . Bred at Eperjes (Aigner- 

 Abafi, in litt., 21, iii, 1907). 



Among the Strymonids, two gynandromorphs of Nordmannia ilicis 

 have been recorded, viz. : 



1. Incomplete gynandromorph ; 3 and ? markings irregularly mixed ; abdo- 

 men ? . Bred at Parchwitz, Silesia [Wiskott, Lep.-Ztcitt., p. 10 (1897)]. 



2. Incomplete gynandromorph ; preponderantly 3 in coloration, with a large 

 orange ? spot on the left forewing ; shape of body 3 . Locality unknown ; from 

 the Karstanjen Collection, in Leipzig [Wiskott, op. cit.~\. 



Genus : Bithys, Hiibner. 



Synonymy. — Genus : Bithys, Hb., " Verz.," p. 75 (1816-1818); Stphs., 

 " Illus. Brit. Ent. Haust.," iv., app. p. 404 (1835) ; "List," 1st ed., p. 16 (1850) ; 

 2nded., p. 15(1856); Tutt, "Ent. Kec," xviii., pp. 131-2 (1906). [Papilio-1 

 Plebeius, Linn., " Sys. Nat.," 10th ed., p. 482 (1758). Papilio, Linn., "Faun. 

 Suec," 2nd ed., p. 283 (1761); Miill., "Faun. Frid.," p. 36 (1764); Hufn., 

 "Berl. Mag.," ii., p. 62 (1766); Schiff., " Schmett. Wien.," 1st ed., p. 186 

 (1775) ; Fuess., " Verz.," p. 31 (1775) ; Miill., " Zool. Dan. Prod.," p. 36 (1776) ; 

 Fuess., " Mag.," i., pt. 2, p. 262 (1778) ; Geoff., " Ent. Paris.," p. 243 (1785) ; 

 Schneid., " Svs. Besch.," p. 221 (1785) ; Lang, " Verz.," ii., p. 47 (1780); Bork., 

 " Sys. Besch.," i., pp. 136, 265 (1788) ; " Bhein. Mag.," i.. p. 295 (1793) ; Hb., 

 "Eur. Schmett.," pi. lxxiii., figs. 369-370 (1799); text p. 56 (circ. 1S05) ; 

 "Raupen," etc., Pap. I., Gens A, c. d., figs. 2a- c (circ. 1800); 111., "Schmett. 

 Wien.," 2nd ed., p. 279 (1801) ; " 111. Mag.," iii., p. 203 (1803) ; Herbst, " Nat. 

 Syst. Ins.," xi., p. 67. pi. 306, figs. 1-4 (1804) ; Ochs., " Die Schmett.," i., pt. 2, 

 p. 96 (1808). [Papilio-Plebeius-] Ruralis, Linn., " Syst. Nat.," 12th ed., p. 788 

 (1767) ; Fab., " Sys. Ent.," p. 521 (1775) ; Bergs., "Nomen.," p. 58, pi. xxxvii., 

 figs. 4-5 (1778) ; Goeze, "Ent. Beit.," p. 10 (1780) ; Fab., " Spec. Ins.," p. 118 

 (1781); "Mant. Ins.," p. 69 (1787); Brahm, " Ins.-Kal.," p. 375 (1791): 

 Schwarz, "llaup.-Kal.," i., p. 47 (1791) ; Haw., "Lep. Brit.," p. 38(1803). [Ple- 

 beius- ) Ruralis, Esp., " Schmett. Eur.," p. 262, pi. xix., figs, la, b, c (cumlarv. et 

 pup.) (1777). [Papilio-] Ruralis, de Vill., " Car. Linn. Ent. Faun. Suec," p. 63 

 (1789). [Hesperia-] Ruralis, Fab., "Ent. Syst.," iii., pt. 1, p. 278 (1793); Panz., 

 " Schaeffer's Icones," etc., 2nd ed., p. 147, pi. clviii., figs. 4-5 (1804). Cupido, 



