NUMBER OF INSECT SPECIES. 53 



cnce upon the habits of the animal, and which, indeed, in 

 many cases, compel us to separate groups which we know 

 to be naturally allied by affinity to each other. Thus we 

 separate the wasps from the bees, because the former fold 

 their upper wings longitudinally when not flying ; and thus 

 we divide the beetles according to the joints of the tarsi, 

 although, in some instances, direct affinities are thereby 

 separated. 



Nevertheless, the great advantages resulting from an arti- 

 ficial method are so obvious, that we find them admitted by 

 persons who do not hesitate to reject, as an absurd fancy, 

 the existence of a natural system. These advantages will 

 appear the more evident when we investigate the actual 

 number of insect species. Our great and pious naturalist, 

 John Ray (" le premier veritable naturaliste pour le regne 

 animal," as the equally great Cuvier has styled him), in his 

 " Wisdom of God," published at the close of the seventeenth 

 century, tells us respecting the number of British insects : 

 " The butterflies and beetles are such numerous tribes, that 

 I believe, in our native country alone, the species of each 

 kind may amount to 150 or more. The fly kind (if under 

 that name we comprehend all the flying insects, as well 

 such as have four, as such as have but two wings, of both 

 which kinds there are many subordinate genera), will be 

 found in multitudes of species to equal, if not exceed, both 

 the forementioned kinds. The creeping insects that never 

 come to be winged, though for numbers they may fall short 

 of the flying or winged, yet they are also very numerous. 

 Supposing then there be a thousand several sorts of insects 

 in this island and the sea near it ; if the same proportion 

 holds between the insects natives of England and those of 

 the rest of the world, as doth between plants domestic and 

 exotic that is, as I guess, near decuple the species of in- 

 sects on the whole earth (land and water) will amount to 



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