( Ixxix ) 



" In his ' Island Life,' when dealing with the British Isles, 

 Dr. A. R. Wallace designates, amongst others, 179 forms of 

 Lepidoptera as being peculiar to the British Isles. This list of 

 species was compiled for Dr. Wallace by Mr. Tutt, and the 

 latter gentleman has supplemented it by a much extended 

 list in his articles on this subject in Vol. XIV of the ' Ento- 

 mologist's Record.' 



"As Mr. Tutt himself remarks, many of the forms 

 enumerated will have to be erased from |the list, as soon as 

 continental entomologists commence to study variation more 

 than is the case at present. The object of the present paper 

 however is not to determine what is and what is not a 

 peculiar British form, but to call attention to constant 

 differences between the prevalent form occurring in England 

 and the prevailing form of the same species from the 

 continent. 



"Having collected formerly for years in England the writer 

 has been a resident in Germany for the last five years, and 

 during this time has had many hundreds of the species 

 mentioned through his hands. Very shortly after his removal 

 over here he was struck by the differences between Mamestra 

 dissimilis (suasa), Pachnobia rubricosa, Orthosia litura, Xylina 

 ornithopus and the forms of these insects as he had known 

 them in England. 



" England is the home of many dark races, Polia chi, var. 

 olivacea, Amphidasys betularia, var. doubledayaria, the dark 

 forms of H. abruptaria, L. multistrigaria, P. pedaria, 0. hiden- 

 tata, etc., and it is therefore all the more curious that in the 

 22 species of Noctuse enumerated the tendency is always for 

 the English form to be lighter and the continental darker. 



" It does not appear to me that the colour of the soil is 

 here a determining factor, as were this the case one would 

 expect Berlin insects to be the lighter, the soil round Berlin 

 being for the greater part a fine yellow sand. Compare this 

 with the London clay on which most of my English captures 

 were made. 



" It is more probable that climatic conditions are the 

 determining factor, possibly the proximity of the sea. I 

 have unfortunately not had an opportunity of collecting on 



