THE DISTRIBUTION, RARITY, OR ABUN- 

 DANCE OF VARIOUS SPECIES 



THERE are few points about which we know less 

 than the causes of distribution and rarity, al- 

 though there are certain tolerably well recognized 

 laws which govern the occurrence of some species 

 in certain localities. What I mean is that 

 marshy spots, say salt marshes for instance, 

 attract certain beetles and bugs which are 

 never found except in such places ; certain 

 kinds of flowers attract bees which never appear 

 to visit any others, but these localities and 

 kinds of flowers occur often at great distances 

 from each other, and why given a certain flower 

 you probably find a certain bee peculiar to it ; 

 or given a certain kind of marsh you probably 

 find a certain beetle, although the localities 

 may be hundreds of miles apart I think still 

 awaits explanation. I will give an example 

 with which I am personally well acquainted. 



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