3 1* 



1884.1 138 



On the duplication of generic names employed hy Wal'ker. — It is well known 

 that certain Lepidopterists ignore the greater part of Walker's work ; but recently 

 my friend Meyrick has employed at least one of the generic names used by that 

 author in a totally different sense from that intended by the original describer. 



The " genus " Barsine was characterized by Walker in the second volume of 

 his Catalogue of Lepidoptera-Heterocera for the reception of a Lithosiid moth 

 congeneric with Miltochrista, but representing a group in that genus consisting of 

 species larger and somewhat more coarsely ornamented than the 31. miniata group. 



The name Barsine has now been applied by Meyrick to a group of Q-eometrites ; 

 and as I find that writers in New Zealand are already beginning to adopt this wrong 

 use of Walker's generic name, I feel called upon, although with reluctance, to point 

 out the error ; I would ask Mr. Meyrick to alter it himself, but, as I may have to 

 quote the genus before many months have elapsed, and as it would be probably a year 

 before I could discover what name he had employed, I must myself propose that 

 the New Zealand genus be henceforth known by the name Meyrickia. — A. G-. 

 Butler, British Museum (Nat. Hist.) : September 26th, 1884. 



On the probable extinction of Lyccena Arion in England. — Mr. Herbert Gross 

 in his intei'esting paper " On the probable extinction of Lycoena Arion in Britain " 

 (c/. Ent. Mo. Mag., xxi, 107), inclines to the opinion that the sudden and total 

 disappearance of L. Arion from the Gloucestershire localities may have been due to 

 an unprecedented succession of mild winters, &c. In this conclusion I can quite 

 agree with him. 



It may be observed, that although the abnormal meteorological vicissitudes ex- 

 perienced throughout Great Bi'itain during the past six or seven years must have 

 not only considerably checked the increase of many species of Lepidoptera, but have 

 also greatly reduced the normal numbers of some other species, still, a series of 

 unfavourable meteorological conditions during a period of several years would hardly 

 lead to the extermination of those species which are generally distributed. Even 

 the not unimportant assistance of the most assiduous collector and an occasional 

 grass or furze fire would fail to effect so much. In the case, however, of local species, 

 the chances of escape from such a combination of hostile agencies would be rather 

 precarious. 



With such species as L. Arion, confined to somewhat limited areas of widely 

 separated districts, there exists what may be termed a predisposition to extinction, 

 and a series of seasons meteorologically unfavourable may effect the extermination 

 of the species, first from one and then another of its limited retreats, until its final 

 extinction in the country would be accomplished. 



By predisposition to extinction I mean, that when the limit of the range of a 

 species is reduced to a very small portion of a district, independent of the range of 

 its food plant, it may be assumed that that species is in danger of extermination 

 from the operation of one or the other, or a combination of several unfavourable 

 conditions. In effecting a " sudden and total disappearance," I should certainly 

 consider unfavourable meteorological conditions to be the prime influence. 



Almost the same remarks will apply to any species of Lepidoptera restricted to 

 the limited habitat of its food plant ; with this additional contingency, the food 



