196 THE ENTOMOLOGIST. 



its points of difference from athalia as follows : — " Aurelia* ist 

 urn I in Ausmass kleiner als athalia, die Flugelform ist langer 

 gestrecht, und in der Farbung herrscht ein dunkleres Braun 

 vor. Die Unterseite ahnelt mehr der von dictynna, obgleich der 

 Silberschimmer der Flecken an den Unterfliigeln mangelt." 

 (This last peculiarity, by the way, is very far from being constant 

 in dictynna.) Nickerl also insists very rightly on the fact that 

 the two species do not fly at the same time as a reason for their 

 being distinct, and though his actual statements as to the times 

 of appearance show that he was under a misapprehension, still 

 the fact itself is conclusive. He speaks of aurelia as flying in 

 the second half of June, when the " first brood " of athalia was 

 worn out, and says that it did not occur again in his neighbour- 

 hood at the end of July and in August when athalia (obviously 

 implying a second brood) was again very common. Now in 

 point of fact athalia is never regularly double-brooded, though in 

 very hot seasons a very partial and very stunted second brood 

 does occasionally occur. On referring back to Nickerl's account 

 of athalia, it is seen that he speaks of it as being very common 

 from May to August, and as he ignores parthenie altogether, 

 except for mentioning incidentally that it is not identical with 

 his aurelia, I think there can be little doubt that under the name 

 athalia he included not only the one brood of that species, but 

 the two regular broods of 'parthenie which precede and follow it. 

 This would correspond to the order of appearance in the Ehone 

 Valley, where the first brood of parthenie is followed shortly by 

 aurelia, then by athalia, which again is succeeded by the second 

 brood of parthenie. In the mountains, for instance at Berisal, 

 at about 5000 ft., aurelia flies at the end of June and the 

 beginning of July, but athalia again succeeds it ; I have also 

 taken one specimen above Zinal at an altitude of about 6500 ft. 

 as late as mid- August, but I have never found athalia at so high 

 an elevation, though if it occurred it would there probably be 

 contemporary with aurelia. It is quite certain, moreover, that 

 Nickerl was a little "shaky" on this group, for he refers his 

 species both to Borkhausen's prtri/?6?iie, which he afterwards says 

 is not the same, and to Hubner's athalia, tab. 4, figs. 19, 20, 

 which certainly represents aurelia, as well as to Esper's athalia 

 minor, tab. 89, which, so far as it can be said to represent any- 

 thing definite, approaches nearest to varia, though the letterpress 

 would seem to point to parthenie.^ North of the Alps this species 

 seems to be single-brooded even in the plains, except in ihe 



* Aurelia is a third smaller in size than athalia, the shape of the wings 

 is longer, and in colour they are of a darker brown. The under side shows 

 more resemblance to dictynna, though the silvery shine of the spots on the 

 hind wing is wanting. 



f Borkhausen, in 1788, when he first iwentions parthenie, a year before 

 he published his Latin description of it, distinctly states that he is speaking 

 of the insect here depicted by Esper. 



