Extinction, of Organic Beings. 4*7 1 



to examine farther into the tenability of Linnaeus' theory of 

 central foci. 



It is evident then that the mountains of the imaginary 

 focus of creation could not have been isolated ; nor indeed 

 is there greater reason to believe that they were connected 

 with various regions of the earth. 



Let us however suppose that they were so, and it will 

 follow, that as the races multiplied, they would extend along 

 those ranges to various countries whose temperatures were 

 adapted to their comfort and well being, and thus in the 

 lapse of years be found in different and widely distant 

 regions of the earth. 



From Ly ell's Principles of Geology, may be derived an apt 

 illustration of the absurdity of supposing that the vegetable 

 and animal kingdoms were originally diffused from a com- 

 mon centre. 



In speaking of the supposed foci of creation, he says, — 

 " let us imagine that about three centuries before the dis- 

 covery of St. Helena (itself of submarine volcanic origin) a 

 multitude of new isles had been thrown up in the surround- 

 ing sea, and that these had each become clothed with 

 plants emigrating from St. Helena, in the same manner as 

 the wild plants of Campania have diffused themselves over 

 Monte Nuovo. Whenever the first botanist investigated 

 the new archipelago, he would meet with individuals of 

 every species belonging to all parts of the archipelago, and 

 some in addition peculiar to itself, namely, those which had 

 not been able to obtain a passage into any one of the sur- 

 rounding new formed lands. In this case, it might be truly 

 said that the original isle was the primitive focus or centre 

 of a certain type of vegetation, whereas in the surrounding 

 isles, there would be a smaller number of species, yet all 

 belonging to the same group."* 



* Lyell's Principles of Geology. 



