THE DECADENCE OF BRITISH LEPIDOPTERA. 103 



occurring in only a few localities, owing to the destruction of 

 woodlands. A. iris is often exterminated, although the woods 

 in which it used to occur still exist, owing to the constant 

 cutting away of the undergrowth during winter and early spring, 

 and the consequent destruction of the hybernatiug larvse. I 

 could give several instances of this did space allow. 



Melitaa athalia, M. aurinia {artemis). — Now extinct in many 

 localities where formerly abundant, chiefly owing to destruction 

 of woodlands and heaths, and (in the case of M. aurinia) 

 draining of marsh and fen-land. M. athalia is now, I fear, 

 extinct as an Essex insect ; in quite recent times it could be 

 taken in two places at least in this county ; both localities have 

 been destroyed for agricultural purposes. 



Tliecla pnuii, Carterocephalus pakemon (paiiiscus). — Both 

 species now cpnfined to a few localities (woods) in our midland 

 counties. It is only reasonable to suppose that both these 

 insects must have occurred freely over the counties in which 

 they have been taken, prior to the destruction of the woodlands 

 of these counties. I consider therefore that their present 

 restricted range, and liability to possible extinction as British 

 insects, to be entirely due to the destruction of their habitats for 

 agricultural purposes. 



Lijccena avion. — Having personally collected in the chief 

 localities in this country where L. arioii is or has been taken, I 

 have formed the opinion that agriculture is practically the sole 

 cause of the now comparative rarity of this species ; even at 

 Barnwell Wold, where large numbers were undoubtedly taken by 

 collectors, the insect did not become extinct until the fields in 

 which it occurred were burnt by the agriculturist. In the 

 Kingsbridge (South Devon) locality this same burning has 

 been the chief cause of its destruction. L. avion still exists on 

 the Cotswold Hills in Gloucestershire, and used to be taken in 

 many other localities in the same county until it was wiped out 

 by agriculture ; its continued existence on the Cotswold Hills is 

 due to the fact that the ground on which it occurs has not been 

 broken up for agricultural purposes. 



I could cite further examples in support of my views, but 

 those mentioned will, I think, suffice. 



Mr. Harcourt-Bath's article refers to British PJiopalocera 

 only, but the evil effects of agriculture (from an entomological 

 point of view) are quite as apparent in the case of many of the 

 Heterocera. 



In conclusion, I should wish, in support of my theory, to 

 refer to the simple fact that it is precisely those locahties that 

 have been the least affected by agricultural operations that now 

 form our best collecting-grounds; witness the New Forest, 

 practically the last stronghold of many of our woodland Lepi- 

 doptera; the broads and feus of Norfolk; the hills and mouu- 



