DISTRIBUTION OF ORGANISMS. 227 



earth's surface which has been superseded in our hemisphere 

 by other strata and a higher type of mammalian organization." 1 



Such being the facts of the case, we are to inquire whether 

 they best agree with the hypothesis of an origin of organisms by 

 special Divine exertion, or that of their origination in Divine 

 power working in the manner of natural law ; and also, if the 

 latter supposition appear preferable, how far the facts agree 

 with the plan of animated nature delineated in the preceding 

 pages. 



It is remarkable at the very first, that there is any variety 

 of species in different regions, more especially as the species of 

 one region usually thrive when transplanted to another of 

 generally similar character in point of soil and climate. Had 

 organisms been produced by special attention taking this 

 according to any ideas we can form of it we might rather 

 have expected to see identical plants in similar countries. It 

 will not avail here to attribute the variation to the cultiva- 

 tion of variety as a principle on the part of the Divine Dis- 

 poser, for the differences evidently follow no such principle, 

 being of various intensities in near and in remote situations. 



^5 



In this consideration, there is a great obstacle to the reception 

 of the special-exertion hypothesis. It seems much more likely 

 that organisms took their rise in germs springing from inor- 

 ganic elements ; which germs being different in accordance 

 with such slight local differences in the combination of the 

 elements as physical studies inform us of, and the external 

 conditions attending their development being also locally dif- 

 ferent, the resulting vessels of life were various accordingly. 

 Such variations of result are exactly of a piece with hundreds 

 of other simply natural events for example, the difference of 

 animals bora at one birth ; and similar natural causes are 

 therefore presumable for them. 



The facts respecting the geographical distribution of 

 organisms are in perfect harmony with the plan of their 

 origin, which, from the geological history, the principles of 

 organic development, and their external affinities, has here 

 been sketched. The plan necessitates the facts of distribution, 

 which the other hypothesis does not. First, a development of 

 vegetable organisms, we shall say, taking place in the sea, it 

 is exactly what we would expect, that they should spread upon 

 the neighbouring shores in every direction, and that we should 



1 British Fossil Mammalia and Birds, p, 69. 



