Phylttic Parallelism in Mctamorphic Species. 427 



of black would be the older, simple black spots 

 at the base of the warts the next in succession, 

 and a connected black transverse band the most 

 advanced state of the development. 



Whether this explanation is correct, and if so, 

 what causes have produced the second change, 

 may perhaps be learnt at some future time by a 

 comparison with the ontogeny of other Saturniidee; 

 in the meantime this explanation receives support 

 from another side by the behaviour of the Genoese 

 local form. If the last stage of the German form 

 has actually commenced to be again re-modelled, 

 then this variety is further advanced in phyletic 

 development than the Genoese form ; and this cor- 

 responds entirely with the theory that in the former 

 the light colour (the orange considered as prelimi- 

 nary to the transformation into green) has already 

 been carried down into the second stage, whilst in 

 the Genoese variety even in the fourth stage only 

 the first rudiments of the colour-transformation 

 show themselves. 



The Genoese form is to a certain extent inter- 

 mediate between the German form of Saturtiia 

 Carpini and the nearly related S. Spini, a species 

 inhabiting East Germany. In this latter the 

 larvae, even in the adult state, are completely 

 black with yellow warts. This form of caterpillar 

 must therefore be regarded as phyletically the 

 oldest, and this very well agrees with the character 

 of the moth, which differs essentially from S. 



