G6 [August, 



seem to account for the extraordinary fluctuations in th? appearance of this butterfly 

 in different years. It appears as though, in the efforts to pi-oduce two broods in the 

 year, the autumnal females always lay eggs, which hatch, but that the larrse are 

 killed by any severe frost, thus locally exterminating the species. Some of those 

 hatched on the coast and within the warm influence of the sea may escape, producing 

 the few specimens seen in the early summer, and supposed to have hibernated, from 

 vrhieh are produced the larger numbers found in favourable seasons in the autumn. 

 This also would explain the moi'e frequent appearance of the insect along our coasts, 

 and especially its comparative regularity of appearance on the warm south coast of 

 England. I can see no better explanation of the periodical appearances and dis- 

 appearances in this country of a species which is constantly abundant in the warmer 

 parts of the continent, and the casual immigration which doubtless goes on in 

 favourably situated districts, is insufiicient to account for the simultaneous appear- 

 ance in numbers of perfectly fresh specimens in remote districts. The hypotheses 

 which used to be put forward, of the prolonged torpidity of the species in the egg 

 or the pupa state, appear hardly more feasible to me than the celebrated suggestion 

 that the eggs are imported "in clover seed." 



It is a curious circumstance, that along with that of Edusa there appeared an 

 early brood of Scopulaferrugalis in considerable numbers. It also appeared first on 

 June 4th, hiding in dwarf sallow bushes in marshy fields, but after a few days was 

 to be found about the road sides, and on and under the cliffs, and at last quite 

 commonly about the garden and fields at home — in fact, everywhere. The specimens 

 of this early brood are always yellower than those disclosed in the autumn, and, in 

 my experience, always very scarce ; indeed, I have, with one exception, never taken 

 them except in the immediate vicinity of the sea. The causes that have affected 

 Collas Edusa ha^e therefore evidently been at work with tliis species. — Chas. G. 

 Bareett, Pembroke : Idth July, 1877. 



Colias Edusa iii Perthshire. — After reading Mr. Sang's notice of the occurrence 

 of G. Edusa in such plenty near Darlington, I wrote to Sir Thomas Moncreiffe to 

 say that I fully expected to hear of the occurrence of this insect in Perthshire. In 

 reply, I heai' as follows : — " A fine male Colias Edusa was well S'cn close to 

 him by Mr. Hird in his garden, about June 22nd. Unfortunately, he had no net, 

 or he could have taken it easily, and, by the time he had fetched a net, the Edusa 

 was gone. lie knows the insect well, and I have no doubt as to his being correct in 

 his statement. — Moncreiffe House, Bridge of Earn: July 2nd, 1877." — H. T. 

 Stainton, Mountsfield, Lewisham : July Uh, 1877. 



[See also "Scottish Naturalist" for July, 1877, p. 117]. 



The recent ahundance of Colias Edusa in Britain. — In connection with this 

 extraordinary phenomenon, it may be not without interest to remark, that having 

 recently travelled over a considerable portion of Belgium, I took the opportunity of 

 enquiring, both of individual entomologists, and at a Meeting of the Belgian Ento- 

 mological Society, whether anything parallel to this had been observed in that 

 kingdom this year. I could not ascertain that the species had been anywhere ob- 

 served up to the first week in JiUy, thus proving, to some extent, that the causes of 

 its apparition in Britain were internal. — R. McLachlan, Lewisham : \2th July, 

 1877- 



