Geographical Distribution of Insects. 371 



that solitary spot where all the present generations have had 

 their birth ! In what manner, then, did they become its deni- 

 zens, or by what means were they transported to a point almost 

 imperceptible in comparison with the immeasurable extent of 

 the circumjacent ocean. These are subjects of inquiry, a few 

 out of many such, which it is more than probable man will never 



solve. 



" In his tam parv'is atque tarn nullis quae ratio ! 

 Quanta vis ! quam inextricabUis perfectio !" 



The primary causes of the distribution of species, as well in 

 the animal as the vegetable world, are, in the opinion of Hum- 

 boldt, among the number of mysteries which mere natural science 

 cannot reach. This science, or the branch of it which takes 

 cognizance of zoological geography, is not, however, occupied 

 in the investigation of the origin of beings, but rather of the 

 laws according to which they are now distributed over the sur- 

 face of the earth. It is the spirit of inductive philosophy ap- 

 plied to the ascertained facts of zoology, as connected with clime 

 and country. It enters into an examination of things as they 

 are, the co-existences of vegetable and animal forms in each 

 latitude, at different heights, and at different degrees of temper- 

 ature ; it studies the relation under which particular organiza- 

 tions are more vigorously developed, multiplied, or modified ; 

 but it approaches not problems, the solution of which is impos- 

 sible, since they touch the origin or first existence of the germs 

 or life. 



Many interesting facts have been ascertained and detailed by 

 scientific observers of late years, which, in a collected form, 

 would serve as the basis of a memoir on animal geography, 

 which, however imperfect, would scarcely be devoid of interest- 

 ing and important results. 



