Pkyktic Parallelism in Mctamorpkic Species. 441 



and the St-siithf possess throughout a 

 characteristic form of larva. 



Of the group Dombycina the family of the Satur- 

 niida possess thick cylindrical caterpillars, of which 

 the segments are beset with a certain number of 

 knob-like warts. It is true that two genera of this 

 family (Endromis and Aglia) are without these 

 characteristic warts, but the imagines of these 

 m ncra also show extensive and common differences 

 from those of the other genera. A distinct family 

 has in fact already been based on these genera 

 (Endromidtc, Boisd.). Thus the congruence is 

 not thereby disturbed. 



So also the families Liparidcc, Euprepiidce, and 

 Lithosiidcc appear sharply defined in both forms ; 

 and similar families occur likewise under the 

 Noctuina, although in this group the erection of 

 families presents great difficulties owing to the 

 near relationship of the genera, and is always to 

 some extent arbitrary. It is important, however, 

 that it is precisely the transitional families which 

 present intermediate forms both as larvae and as 

 imagines. 



Such an instance is offered by the Acronyctidte, 

 a family belonging to the group Noctuina. The 

 imagines here show in certain points an approxi- 

 mation to the group Bombycina ; and their larva;, 

 which are thickly covered with hairs, likewise 



appears probable that they are nut related to the 

 note i, p. 370. R.M.] 



