1S79.] 51 



To turu again to our own islands, the insect has been generally 

 abundant, at any rate in the south of England, but I do not know 

 that at any place has it been observed in columns, nor that any par- 

 ticular direction of flight has been recorded. Mr. Buckler {in litt.) 

 truly observes that " V. cardui is master of the situation," and he 

 remarks that they flew with him regardless of the rain, though one 

 individual did show signs of wishing to share with him the shelter of a 

 stable in which he had taken refuge. I saw an utterly worn indivi- 

 dual, flying in a wild manner, so late as the 19th of this month (July). 

 So far as I can learn, the species was tolerably common last autumn, 

 but not in a degree to account for its abundance this year. 



There can, I think, be little doubt that all the swarms consisted 

 of individuals that had hibernated ; there can, also, be little doubt 

 they were migratory, and that the columns had become dispersed 

 before remnants of them reached our shores, and other parts of the 

 N. of Europe. It is by no means the first time that records of the mi- 

 gration of V. cardui have been published. One such, in the harbour 

 of Corfu, is noticed in this Magazine (vol. ix, p. 149) by Dr. Buchanan 

 White, on the authority of Colonel Drummond Hay. But never before 

 have the swarms been so general, and of such an extent. That their 

 flight was more or less from S. to N. appears certain. Whence came 

 they ? This we probably never shall know, nor why, in a season like 

 this, they should fly from climes that certainly should be more genial, 

 to experience the cold and cheerless spring and summer (so-called) of 

 1879 in the inhospitable north. Were they all bred last autumn ? ; or 

 is it possible the insect may be able to rest quiescent in the perfect 

 state over a series of years, until the accumulated numbers simul- 

 taneously wake up? If this be anything more than a rash conjecture, 

 why has this season of all others induced a termination of their 

 Eip-van- Winkle-like slumbers ? 



The whole subject is surrounded with difiiciilties ; more so than 

 was that of the great abundance of Colias Edusa in these islands in 

 1877, because that phenomenon only concerned these islands (the spe- 

 cies not having been noticed in any exceptional numbers on the 

 Continent) ; and I think it has been proved that with it the pupa- 

 state can be prolonged over several years : at any rate, I know of 

 pupse now living (or, at least, they were alive a month or two ago) the 

 produce of eggs laid by the butterflies of 1877, and which hatched in 

 due course. 



Lewisliam, London : 

 July, 1879. 



