44 



have the hind wings at one time ample, at another rudi- 

 mentary, and at a third nearly obsolete. Now, although 

 other causes, hereafter to be noticed, would seem to have 

 far greater power than climatal ones in permanently 

 regulating the size and capacity of these appendages ; I 

 think it will be found on examination (and I may add 

 that Mr. Westwood is of the same opinion *), that the 

 greater or less development of them may be frequently 

 explained by the unusual severity of the seasons. 

 own researches would certainly tend to prove, that heat 

 does (in the main) favour, and cold retard, their pre- 

 sence. Exceptions (often rendered intelligible from 

 the evident working of counter influences) will of course 

 arise in abundance to this hypothesis ; yet my impression 

 is that, upon a broad scale, it will stand the ordeal of a 

 rigid inquiry. 



Speaking of certain representatives of the Hymen- 

 optera (Chalcididce), Mr. Westwood observes: "A 

 curious peculiarity exists in one at least of these 

 apterous species, which has been noticed by no previous 

 author, namely, Choreius ineptus, Westw., which, 

 although ordinarily found in an apterous state, was 

 discovered by me in considerable numbers during the 

 hot summer of 1835, with wings t". And, touching 

 the irregularity of the alary organs in the Homopterous 

 Fulgorida, he remarks : " Other instances, in which the 

 wings undergo a deficiency of development, occur in the 



* Introduction to the Modern Classification of Insects (London, 

 1840), ii. p. 4/3. t Id. ii. p. 158. 



