56 



Having then disposed of this preliminary appendage to 

 our inquiry, by expressing our belief (which I am satisfied 

 that observation will tend more and more to corroborate) 

 that certain countries and spots are by constitution more 

 favourable than others for the increase (apart from the after 

 dissemination) of the insect tribes, and that too through 

 local influences amongst which mere heat and cold are 

 but secondary in importance ; let us proceed to consider, 

 how far the nature of the several districts may assist us 

 in accounting for some of those numerous aberrations 

 from the typical state which various insects are accus- 

 tomed to display, and on which it has too often hap- 

 pened that " species " (so called) have been attempted 

 to be established. I may premise however, that, whilst 

 (as already urged) I would regard climate per se as sub- 

 sidiary to many other agents, I would not wish to 

 ignore its action altogether even under the present sec- 

 tion, since in combination with peculiar circumstances 

 and conditions it may have (and probably has) consider- 

 able controlling power : nevertheless I would desire it to 

 be looked upon here as, at any rate, an inferior element, 

 and as working in conjunction with physical influences 

 of greater significance than itself. If therefore under the 

 preceding heads it has been treated (so far at least as the 

 exceptions would permit) as a great geographical principle, 

 possessing a certain modifying quality on a large scale, 

 let us now merely recognize it to the extent in which we 

 are actually compelled to do, when dealing with areas of 

 smaller magnitude, namely as a topographical one. 



