HISTORY OF MEXICO, 



19S 



Armenia, had been collected on the American Alps, by 

 the fame way of reafoning the number of fpecies of qua- 

 drupeds in the old continent would have been lefs, and 

 the American philofopher would have been liable to cen- 

 fure, who, from fuch an incident, would have endeavour- 

 ed to infer the prodigious fcarcity of matter, and bar- 

 ren niggard fky of that which we call the old continent. 



But although all thole quadrupeds were actually ori- 

 ginal in America, we ought not from thence to infer the 

 luppofed fcarcity of matter, becaufe a country cannot be 

 faid to have a fcarcity of matter which has the number 

 of fpecies of its quadrupeds proportioned to its extent. 

 The extent of America is the third part of the whole 

 earth, therefore it cannot be faid that there is a fcarcity 

 of matter there, when it has a third part of all the fpecies 

 of quadrupeds. The fpecies of quadrupeds, according 

 to BufFon, are two hundred, of which America has fe- 

 venty, which is fomething more than a third ; it cannot 

 therefore be faid that there is a fcarcity of matter there. 



Hitherto we have reafoned on the fuppofition that 

 what Mr. BufFon has faid was true with refpecl: to the 

 number of fpecies of quadrupeds ; but who is certain of 

 this, as the real diflinguifliing character of fpecies has 

 not yet been difcovered ? Mr. BufFon, as well as feve- 

 ral other naturalifts who have written after him, believe, 

 that the fole indubitable proof of the fpecific difference 

 of two animals, fimilar to each other in many circum- 

 flances and properties is, that of the male not being able 

 to cover the female, and of producing by means of ge- 

 neration another individual that is fruitful and fimilar to 

 themfelves. But this proof of diverfity of fpecies, be- 

 fides that it fails in fome animals, is, with refpecl: to 

 others, very difficult to be determined. To fhew the 



Vol. III. C c uncertainty 



