126 THE ENTOMOLOGIST. 



icarus in some localities, is still associated with it by forms 

 occurring in other localities, as, for example, in Ireland and 

 Scotland. Escheri and eros may be species in the ordinal-}^ 

 acceptation of that terra, but they are not so distinct from icarus 

 as are ylieretes, orhiUdus, and anteros, descendants of the same 

 original stock, but by another line of which astrarche is the 

 dominant form. Cory don and hellargus probably stand in the 

 same relation to each other as do icarus and hylas. 



When considering the under-side variation of corydon {ante, 

 p. 8), I suggested that if individuals varying little or much in any 

 one direction could be removed apart, the type of aberration, 

 possessed in different degrees b}^ the individuals set down, would 

 beome specialised. Of course such a result would depend (1) on 

 the locality selected for colonisation being a suitable one, and (3) 

 on the new colony being free from any chance visits of the 

 typical or otlier forms of the species. Suppose, however, some 

 such experiment to have been successful, and a race of more or 

 less uniform aberrations to have been developed, we should still 

 find tbat the earlier stages of the aberration would occur among 

 the type form, and these minor varieties would connect the 

 aberrant race with its parent type. Of course in this case, from 

 our knowledge of its origin, we should not consider that we had 

 established a new species; but if such a race had been developed 

 in the ordinary course of evolution, — I mean without man's 

 assistance, — we should have no knowledge of its history, and 

 consequently should have some difficulty in determining its rank. 

 Should we, however, know that examples of an allied species 

 occasionally varied in the direction of the special character of 

 this race, we should, I think, be justified in assuming that it was 

 a local form of the species among which similar aberrations 

 occurred. A case in point is that of L. eros var. candalus. Some 

 entomologists consider this a distinct species, whilst others only 

 allow it to be a form of eros. Whether considered as a species or 

 a form of eros, or even of icarus, it is equally interesting as an 

 example of one of the modifications which have occurred from 

 time to time in the development of the several insects we have 

 had under consideration. Why certain forms should be selected 

 for specific rank, and others, which have distinctive characters of 

 equal merit, be considered merely local varieties, I know not. 

 Take corydon var. albicans for example. Does anyone see specific 



