LÉPIDOPTÉROLOGIE COMPARÉE 4/3 



incidentally it appeared that hirtarïa and fomonaria occa- 

 sionally yielded grey larvas. It is precisely in those points in 

 which zonaria is nearest to the phylogenetic (and therefore 

 common) ancestor of ail the forms, that the hybrids approach it, 

 that is to say, there seem to be latent in hirtaria and the others, 

 common characters, which are once more brought into being in 

 the liybrid owing to their persistent occurrence in zonaria. It is 

 fair therefore to assert, that, if in hirtaria, lapponaria and pomo- 

 naria, we could ûnd a single character nearer to the ancestral 

 form than in zonaria, that character ought to be reproduced in 

 the hybrid. We hâve just such a character in the pupae (and in 

 a minor degree in the transverse bars in the larvae). The pupae 

 in hirtaria, Lapponaria and ponionaria are of the usual redbrown 

 colour, whilst in zonaria, they are of a specialised yellow brown 

 tint. 



The hybrids follow hirtaria, etc.. Our assumptions are justi- 

 fied. The apparent dominance of zonaria is reduced to a récur- 

 rence of ancestral characters more strongly expressed at the 

 présent time in zonaria, than in hirtaria, etc.. 



If this be true, when one crosses hirtaria and pomonaria, the 

 progeny ought to approach hirtaria more closely than pomonaria 

 and this they do, for when I hâve presented larvas or imagines, 

 either of hunii or pilzii, to friends they hâve always named them 

 aberrant hirtaria. 



Hence the phylogenetically older species will always appear 

 to hâve the greater influence or, to put it otherwise, when hybri- 

 dised will always appear to adhère longer to its characters. 



Further, ail the hybrids in which zonaria took part, appeared 

 to hâve the habits of zonaria, both in the larval and imaginai 

 conditions. Well, this is, for the most part, a matter of structure. 

 They are precisely the mean in this respect of the two parents : 

 take the larvae as examples, the claspers are much shorter say 

 in denhami, than in hirtaria. The larvas, therefore, tend to drop 

 and to act as those of zonaria; similarly with other points. 



