ON THE GENUS AGROTIS. 95 



one hand, to A. aquilina and A. ohelisca on the other, and this, I 

 think, points to the conclusion of a common origin of these 

 species, aquilina and ohelisca being two divergent forms of 

 Agrotis tritici. 1 believe, in some northern localities, A. ohelisca 

 is taken without A. tritici, but this might be only a case of the 

 adaptation of this particular form to a certain district, as is the 

 case with the diiferent forms of GnopJia ohscuiriria and Boarmia 

 repatidata. In the south, I believe every locality that produces 

 A. ohelisca or A. aquilina also produces A. tj'itici, while a few 

 places, of which Deal is one, produces all three forms. The insect 

 taken in Ireland under the name of aquilina is much less distinct 

 than many of our own well-marked forms, and would I think at 

 once be referred by entomologists who know A. tritici in the 

 South of England rather to that species than to A. aquilina. I 

 have been unable to get Irish A. ohelisca, but understand from a 

 valued correspondent on the west coast, that, although he 

 believes A. ohelisca occurs there, he is unable to distinguish 

 them ; and although I have received a large number of good forms 

 of A. tritici, I have never got one at all approaching A. ohelisca. 

 These three so-called species seem to be rather mixed up ; but 

 until some very strong proof is urged in favour of their being 

 distinct, I shall look upon them simply as forms of one and the 

 same species, of which A. tritici is the type, and A. aquilina and 

 A. ohelisca divergent forms. 



Before concluding this note, I should like to add that I took 

 some very extreme and beautiful forms of A. cursoria, some 

 of them closely resembling the Shetland forms. A. valligera 

 (which occurred abundantly) also varied very much, two or 

 three specimens being pale and almost devoid of markings, while 

 a few were intensely dark. A. puta, A. suffusa, and A. nigricans 

 swarmed. The latter is a very distinct though variable species, 

 and it seems rather out of place in our lists, between the closely 

 allied A. cursoria and A. tritici, which in the pale forms seem to 

 hug one another very closely. I was also fortunate in securing a 

 fine male specimen of A. lunigera, which I believe is new to the 

 Deal district. 



Another important fact I think worth record is, that out of 

 some hundreds of specimens of this genus captured there 

 seemed to be an almost total absence of forms of a brown 

 colour ; pale grey forms and very dark (almost black) forms 



