457 



logical, or even structural, adaptation may follow the psychological, but 

 as secondary to it. This is only saying in other words that the central 

 nervous system, on whose special functioning peculiarities of habit de- 

 pend, is subject, like any other, to adaptive variations, and that these 

 variations may either follow and reinforce those of some other organ 

 or organs tending to the tame end, or that they may arise independently 

 of any other ; and this is merely extending to insects a generalization very 

 obvious with respect to man, finding warrant for the extension, as we 

 do. in the facts disclosed by an examination of the general economy of 

 insect life. 



Note. — Changes of nomenclature since this paper was written call for the fol- 

 ing data of syonymy : 

 Pp. 449. 453, 456. 



Aphis maidiradicis ^ Anuraphis maidi-radicis (Forbes). 



Lachnostema = Phyllophaga. 

 Pp. 450, 454, 455. 



Emphytus maciilatu^ = Empria maciUata (Norton). 



Phoxopteris comptana = Ancylis comptana (Frohl.). 



Typophoriis aterrimus = Paria canella (Fab.). 



Scelodonta nebuiosits = Gi-aphops nehulosus (L.ec.). 



