8o porritt: vanessa cardui and plusia gamma in 1879. 



about the same date, from mountain ash, at Sandburn near York. 



Boarmia roboraria. Mr. Thomas Foster of Selby took 

 this species not uncommonly at Bishop Wood in July. 



Vanessa antiopa. One was seen, though not captured, 

 in the autumn by Mr. John Smith of Bramham, 



abundance of VANESSA CARDUI AND PLUSIA GAMMA. 



The periodical abundance of various species in different 

 seasons has always been one of the most perplexing problems to 

 the lepidopterist ; and even now we seem as far off as ever from any 

 satisfactory solution. As surely as each season commences there 

 is a general expectation that some species or other will turn up in 

 it in altogether unusual numbers ; though hardly anyone will 

 venture to hazard an opinion as to what species it will be. If he 

 do happen to be so rash, he is pretty certain to name one entirely 

 different from what proves to be the case, and probably even in 

 a widely different family ! 1865 is known as 'Hhe Celerio year;" 

 and since then we have had a '■'• Lineata year;" a ^'' Lathotiia year;" 

 a '■'' Pulchella year" and others. 1872 was the "great Antiopa 

 year;" 1877 the '■^ Editsaytaxf whilst last year, 1879, an invasion 

 of Plusia gamma and Vanessa cardui overran the land. The 

 entomological journals will have given us all a tolerably clear 

 idea of the prodigious numbers of both species contained in this 

 invasion. Suffice it to say that both in Britain and on the Con- 

 tinent of Europe, probably in all parts of it, has gamma swarmed 

 in countless thousands, both on the sea-coast and inland. 

 Writing from Bournemouth of V. cardui and P. gamma, Mr. 

 McRae says, (Entom. p. 222) "the former are swarming in 

 thousands, and the latter in tens of thousands. With the doubtful 

 exception of gnats on a calm summer evening, I have never seen 

 any species of insect so multitudinous." Mr. Joseph Anderson, 

 Junr., of Chichester, recorded whole fields of peas being well nigh 

 stripped bare of leaves by the larvae oi gamtna, the moths swarming 



Trans.V.N.U.,1878. Series D 



