222 THE ENTOMOLOGIST. 



" outer " and " inner.'" The fringes on both sides of both wings 

 are yellowish white, chequered with black or blackish. 



Beyond the passages already quoted there seems to be little 

 help towards finding distinguishing marks between these species 

 in the earlier lepidopterists. Ochsenheimer distinguishes j)ar- 

 thenie from athalia by (1) its smaller size ; (2) its longer wing- 

 form and finer markings ; (3) its later emergence, and absence 

 from many of the localities of athalia. Like most, if not all, of 

 his predecessors and contemporaries, he ignores the fact that it 

 is double-brooded, and emerges before as well as after athalia. 

 Berce, Bergstrasse, Boisduval, Borkhausen, Duponchel, Esper, 

 Freyer, Godart, Herbst, Herrich-Schaffer, Hiibner, Knoch, 

 Latreille, Schiffermiiller, Schneider, Wallengren, and others 

 have been tried in vain ; but Meyer-Dur's illustrations show 

 that in his time (1851) the terms athalia, parthenie, and aurelia 

 were used — in Switzerland, at any rate — in precisely the sense 

 in which they are used to-day. Modern authors, too, are but of 

 little assistance in this matter. Neither Frey nor Favre give 

 descriptions ; I have found nothing to elucidate the matter in 

 Oberthiir ; and, turning to English authors, matters are even 

 worse. Lang's descriptions are slight and his distinctions not 

 reliable ; Kirby's are somewhat fuller, but unfortunately are not 

 consistent with facts ; and even Kane is neither so clear nor so 

 correct as one always expects to find him, a fact of which he 

 himself makes full acknowledgment. A fairly exhaustive (and 

 wholly exhausting) search through the entomological journals 

 has revealed little but regrets and complaints at the difticulty of 

 the group, the most valuable remarks in the English journals 

 being contained in Kane's note in the * Entomologist ' for 1886, 

 p. 145, on the instability of the species of this group, though I 

 cannot concur in his theory as to the relationship of the plain 

 and mountain forms, which, however, has strong advocates. To 

 all this one grand exception stands out in the person of Piiihl, 

 who, in the ' Societas Entomologica,' has a monumental work 

 on the subject, extending through six numbers in its fourth year 

 and ten in its fifth. Of course he also deals at length with 

 these species in his Palsearctic Butterflies, but for our present 

 purpose his work in the ' Societas Entomologica ' is the more 

 valuable. This paper deals nominally with three species only — 

 athalia, parthenie, and aurelia ; but, as it includes herisalensis 

 under the first, varia under the second, and britomartis under 

 the last, we are left with only three forms — asteria, dictynna, 

 and the typical deione — untouched, and these, generally speak- 

 ing, the most easily distinguished. Parts of this paper I have 

 embodied in the following descriptions of the various species, to 

 much more I shall have to refer when speaking of the variation 

 of the group ; at present I must content myself with certain 

 definite acknowledgments, and a few criticisms of the points on 



