27 



assistance (whilst examining insect-variation, with re- 

 ference to climate) from the consideration of a fact thus 

 seemingly important, since there are but few species 

 whose range is so comprehensive as to embrace, at the 

 same time, the equatorial and temperate regions of the 

 earth ; and since, as lately suggested, it is not from a 

 comparison of the aborigines of countries far removed 

 that we can hope to derive much positive information 

 during our present inquiry. It may be useful however 

 to speculate, why the creative energy should have been 

 thus lavished, as it were, in the torrid zone, whilst the 

 fauna of the cold north is so unpretending and sombre. 

 I believe that in the actual number, both of individuals 

 and species, which they contain, the difference is not so 

 great, between the two latitudes, as might be imagined; 

 and that, were the minims of Scandinavia to be suddenly 

 magnified into the giants of Brazil, the Laplanders and 

 Swedes might stand a fair chance of being temporarily 

 alarmed : nevertheless, as regards the multitude and 

 eccentricity of her forms, there can be no question in 

 which field it is that Nature has ever delighted more 

 particularly to sport. 



Laying aside, therefore, the numerical statistics from 

 our account, is not the exuberance of the tropics at once 

 responsive to the conditions imposed upon them ? Do 

 we ask why it is that the insect population is there 

 moulded upon a type comparatively so colossal ? let the 

 redundancy of the vegetation reply. Have not, also, 

 more rapid laws of putrefaction and decay been pre- 



