472 LÉPIDOPTÉROLOGIE COMPARÉE 



through Lycia to Pœcilopsis, a passage f rom white through yellow 

 to red. 



It is thus seen that the period of séparation between hirtaria 

 and zonaria has been very long, and in spite of the fact that 

 hirtaria possesses a winged female, I gather from the colouring 

 of the imago, and from the colour and structure of the larva, 

 that zonaria, in many characteristics, but not in ail, more closely 

 resembles the ancestrai form, that is, zonaria is phylogenetically 

 the older form ; this is confirmed by the sporadic appearanœ 

 of grey larvas in the highly specialised larvae of hirtaria, lappo- 

 naria, rachelœ and pomonaria. 



In spite of this, one must not assume that zonaria is to be 

 regarded as a primitive type, for it can easily be proved to be 

 specialised in other points. To give one example, the transverse 

 white bars of ail the species in the early larval stages are not 

 confined to this somewhat compact group. They appear in other 

 members of the family e. g. Boarmia crepuscularia, Selenia lu- 

 naria, etc.. Now, zonaria loses thèse bars early, whilst in pomo- 

 naria and hirtaria they persist to the end. It is but fair to assume 

 that the larva which has lost them is the specialised form in this 

 respect. 



It will be seen that the phylogenetically longer separated 

 /. italica and L. hirtaria are nearer in outward appearance al- 

 though not physiologically than are the two gênera Lycia and 

 Pœcilopsis. 



B. The apparant dominance of zonaria. 



Looking at the imagines and larvae of the hybrids we are 

 struck by the great influence zonaria seems to hâve on those in 

 which it occurs, as does grœcaria on the one hybrid in which it 

 took part. Why should this be? What advantage has zonaria 

 presumably a weaker form ? 



As has been shown above, in the colour, both of the imago and 

 of the larva, zonaria more closely approaches the ancestrai form; 



