ARCTIIDA£. 245 



sea, where doubtless they have obeyed a natural instinct in 

 settling down as soon as they descried suitable ground. 

 Among coarse herbage in the more sheltered spots on the 

 cliffs, stubble-fields — where Myosotis arvensis grows in plenty 

 — turnip-fields, weedy banks, and similar, more or less 

 sheltered, spots seem to be most frequently chosen. When 

 disturbed, the moth flies but a short distance, settling again 

 in a similar place, and from folding or almost rolling its 

 wings tightly around it as it alights, looks much like one of 

 the grass-frequenting moths of the genus Cramhus, but it is 

 shy and easily disturbed again. When captured it falls as 

 though dead to the bottom of the net. It has been seen to 

 be attracted by flowers in the sunshine, here more especially 

 by those of Heliotrope ; but abroad by Rosemary, Myrtle, Cist us, 

 Trifolium and Ci/tisus, and while flying round them, from its 

 white colour, has a resemblance to the common white butter- 

 flies. Doubtless the females, on arrival, deposit eggs ; and 

 there is equally little doubt that a few of the resulting larvce 

 in favourable seasons arrive at maturity, since the moths are 

 occasionally taken in the most perfectly fresh condition ; but 

 the peculiarity of the larva, already noticed, of refusing to 

 feed except in sunshiny weather, combined with our some- 

 what inclement climate, appears to put a stop to the natural 

 increase, or even permanence of the species. It is necessary 

 to insist the more strongly upon this, because the insect is 

 clearly double-brooded at least, perhaps triple, wherever it is 

 able to maintain itself ; and here, when reared, the larvee 

 feed up quite rapidly — in a fortnight even — and remain but 

 a short time in pujoa ; while the moth is scarcely ever found 

 with us except in the autumn — a time when its rapid 

 increase abroad has evidently induced migration in a species 

 clearly predisposed to such a movement. If it were perma- 

 nent with us, however rare, the occurrences of specimens of 

 an earlier brood would surely be as frequent as those of the 

 later. It was noticed by our earliest writers, always as a 

 rarity, but has been taken in very many years, perhaps 



