26 NATURAL HISTORY OF PLANTS. 



are so much indebted, may at long intervals be increased or dimi- 

 nished, nay, in certain periodical and stated times, be entirely ex- 

 tinguished, and that then, as at first, by the returning splendour of 

 the sun, acting on the ruins of the former creation, and the fer- 

 mentation of the elements, another new one may arise. The peri- 

 odical brightness and faintness of the light of some of the fixed 

 stars, and the total disappearance of some of them which once shone 

 with great splendour, seem to confirm the above opinion. 



But though these remains of pristine animals and plants have 

 been preserved to our times, still it is certain that their originals are 

 not now to be found ; and that our chronology is not sufficient to 

 ascertain the period when changes so eventful have taken place. 



With respect to the plants at present existing on our globe, expe- 

 rience shews that mountainous places are richer in vegetables than 

 plains, and that where there are primitive mountains, the number 

 of plants is more considerable than on secondary mountains. A 

 country where there are primitive mountains, has peculiar plants, 

 which are wanting where there are no such mountains. We find 

 upon ail plains in the same latitude, however extensive they may 

 be, the same plants without any other difference, than what arises 

 from the difference of soils. Upon the primary mountains, and at 

 their feet, we meet again with all the plants of the plains. We find 

 where high chains of the primary mountains skirt the plains, that 

 all the plants of the plain are found at the bottom, and even 

 up their sides. If we pass over the mountain, and come to a new 

 plain, another vegetation appears, which we again find at the feet 

 of the succeeding chain. From the enumeration of plants made in 

 different countries of Europe, and of other regions, we find this 

 abundantly proved. Who then can doubt the plants of all vallies 

 have been derived from high mountains, and that the primary ones 

 of our globe are the source of the Floras of every different country 1 

 Hence it is that America abounds so much in plants, being inter- 

 sected from the North to the South Pole, by high chains of moun- 

 tains, with their numerous branches. Hence Canada produces 

 oiher plants than Pennsylvania, this others than Virginia, this again 

 others than Carolina, and Carolina others than Florida, and so 

 forth. Hence it is that the North-west coast of America nourishes 

 very different plants from the North-east coast, the South-west 

 coast different plants from the South-east coast. Islands that are 



