28 THE ENTOMOLOGIST. 



var. montivaga (= myricai), and several non-British species which 

 are light in Central Germany change similarly to a melanic shade. 



Thus far this paper is a mere record of facts, which it is 

 within the reach of any entomologist to verify on his next 

 autumnal tour on the Continent ; hut the inference can he drawn 

 that we originally owe our insular fauna to migration from the 

 south, and that melanism is primarily due to the peculiar 

 geographical position of these islands. This wave of migration 

 was arrested on reaching our most northern shores with the 

 natural outcome of stunted forms, and melanism became the 

 result of the want of the accustomed succulent food, and of a 

 climate, warmer certainly than that within the Arctic Circle, but 

 still sufficiently cold and with sufficiently short summers to arrest 

 the development capable in the milder climate of the insect's 

 original home. The appearance of melanism in the high 

 mountainous regions of continental Europe, where the same . 

 causes obtain, as in our extreme north, help to support this 

 view. Yorkshire melanism may be treated as merely local 

 aberration, not affecting the general question. 



In these days of close enquiry it is rather surprising that no 

 lepidopterist has thought of rearing some of our Shetland 

 species from the egg, — say Noctua f estiva, which is a conspicuous 

 and common example, — and experimenting whether the succulent 

 food and milder climate of Southern England will not, in one or 

 two generations, reproduce our southern form. 



Writing this paper leads on to an expression of regret, which 

 must be felt by many, that we have in England no central body 

 to look up to for information and reference. In these days of 

 progress it may be worth the consideration of the Entomological 

 Societ}' of London, since its incorporation b}' Royal Charter, to 

 place itself in touch with provincial societies, and make itself in 

 reality the head and exponent of British Lepidopterology. 



New Walk House, Beveiley, E. Yorks, January, 1887. 



ON THE "L72'J" GROUP OF THE GELECHIID^. 



By J. W. TuTT, F.E.S. 



Can any of our entomologists give me any information with 

 regard to that part of the Lita group of the Gelechiidae containing 



