66 BRITISH LEPIDOPTERA. 



removed from the outer margin, but on the under surface*" it is 

 quite at the outer margin. The part of the underside of the fore- 

 wings which projects beyond the hindwings is somewhat duller than 

 the prevailing wing colour; this colour also shows itself somewhat 

 on the underside of the hindwings just before the fringes." Schrank's 

 reference to Linne's Fauna Suecka, no. 1106, which is described as 

 "Pallide ferrugineus, aliis obscure ferrugineus ; alae omnes utrinque 

 fascia arcuata flava; punctum album in medio alae; litura flava ad 

 basin alarum superiorum," is due to Linne's mention of .the yellow 

 epaulette. Esper (on whose figures the name roboris largely depends) 

 writes (Schmett. Eur., hi., p. 84): "There are two veiy different 

 races of this moth, which I have figured on the two accompanying 

 plates. I have observed no difference in the larvae ; perhaps the 

 food and habitat have produced the difference. The larva that 

 produced the moth figured on pi. xiii., figs. 2 — 3, fed on willow, 

 but that from which the moth on pi. xiv., figs. 1 — 2, came, fed on 

 broom. Yet this difference is not an essential one. In the two 

 kinds the colour shows considerable divergence. The male of pi. 

 xiii., fig. 2, is ' weichselbraun ' towards the outer side. A very 

 broad, light ochre-yellow, somewhat curved band, runs through the 

 middle of both wings, but is lost towards the outer margin in the 

 brown-yellow colour. The 2 is of an almost unicolorous pale 

 ochre-yellow colour, and only darker tinted towards the body. 

 The brown-margined white spots in the middle of the forewing are 

 alike in both. The form figured in pi. xiv., figs. 1 — 2, is different. 

 Here the 3 has a deep, dark, 'weichselbraun' ground colour, and a 

 narrow, bright, yellow-coloured band runs sharply defined through 

 the ground colour without losing itself therein. The ? is 

 reddish -yellow; the wings darker towards the body and also 

 at the border of the bands ; I have compared examples from other 

 districts which, in colour, almost agree with the $ . They breed 

 true, yet they are not different enough to form distinct species. 

 Rosel has figured -both sexes of the latter kind at pi. xxxv., figs. 

 4 — 6." One must largely depend on Espers description for a 

 clear idea of what the two forms, to which he refers, really are, 

 for his pi. xiii., fig. 2, represents a S que reus (highly coloured) 

 with the transverse band extending considerably towards the outer 

 margin without reaching it, whilst, on the hindwings, the band is 

 almost typical, just a little broad, and shading off gradually into 

 the slightly darkened marginal colour. It is clear that ab. roboris 

 is, therefore, really but a slight aberration of the type, having 

 wider transverse bands, and must not be confused with ab. guillanotii, 

 Trim., or ab. marginata, n. ab. 



0. ab. guillemotii, Trim., "Actes Soc. Linn. Bord.," xxii.. pp. 31 

 —32 (1859) ; Berce, "Faun. Fr.," ii., p. 191 (1868); Warburg, " Ent. Rec," 

 xiii., p. 238 (1901). Roboris, Stand., "Cat.," 2ml ed., pp. (><), 423 (errata) 

 (1871) ; 3rd ed., p. 121 (1901) ; Holm., " Gross - Schmett.," p. 53 (1887); 

 Tutt, "Ent, Kec," viii., p. 303 (1896); Seebold, ••Ann. Soc. Esp.," xxvii., 

 p. 124 (1898). — This very remarkable form ( j and ?) almost entirely re- 

 places the type in the Gironde district, and differs from the latter in that 



* There appears to be some confusion in the various translations of the original 

 between "under wings" and "under surface." The diagnosis (supra) makes it 

 quite clear that it is "on the underside that the whole outer half of the wings" is 

 yellow, and not the "outer half of the hindwings," as Staudingef notes in his diagnosis. 



