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ESSAY 



ON THE 



CtEOCtRaphical distribution 



OF 



OPHIDIANS, 



Ix proposing to give, in the following pages, a sketch of 

 the distribution of Serpents on the surface of the globe, I 

 consider it necessary to enter into numerous details, with 

 which I might have dispensed, if this part of the science 

 had been previously cultivated, or if any one had al- 

 ready laid the foundations. I have occupied myself with 

 considerable zeal in this study, which merits an espe- 

 cial attention — not merely because it regards the animals 

 of which I treat in my work, but because it ought to 

 lead, in my opinion, to results much more satisfactory than 

 the study of the geographical distribution of the animals 

 in the other classes of the Animal Kingdom, or even of 

 Vegetables. The reasons in favour of this proposition 

 are obvious. A thousand different agents contribute to 

 disperse different species of plants over the surface of the 

 globe : the seeds of plants are carried by the winds and 

 the waves ; man perpetually transplants a great number 



