Rerriarlis on the Ancient Flora of the Earth. 125 



the undisputed fact, that, during the third period of vegetation, 

 there may, in a part of the earth's surface, have been plants which 

 correspond in all their known characters with those of the first 

 period. But what, at the first look, may almost seem still more 

 remarkable, is the circumstance, that these plants, in regard to 

 the part which they, arranged in families, take in the general 

 Floi-a of the globe, shew a similar deviation from the principal 

 characters of the vegetation of these periods of formation. After 

 the great development of the vascular Cryptogamia^ we here 

 observe the same remarkable predominance of that class which 

 is peculiar to the Flora of the old coal formation. These re- 

 markable anomalies by no means appear to us of much conse- 

 quence. If we enquire into the general causes, which we may 

 ascribe to the universally recurring peculiar character of the 

 vegetation of the oldest periods of organic creation, we will 

 find, in the acute observations of our author, a key to the solu- 

 tion of this apparent contradiction. For M. Brongniart, in his 

 treatise, so often referred to (p. 244); has proved as cautiously as 

 convincingly that the character of the Flora of his first period 

 correspond perfectly with characters of the Flora of the present 

 islands, and this agreement is the more striking, the more the 

 islands are scattered in the main ocean, and the farther they are 

 from great continents. What prevents us from concluding, that 

 in those periods also of middle secondary formation, the same 

 operations may have been produced by causes precisely similar .'* 

 For if the present magnitude of the continental masses rising 

 above the water, is not able to completely obliterate the import- 

 ant difference between a continental and an insular Flora, how 

 much more may we not, from good grounds, expect the same 

 difference in those periods in which the influence of great con- 

 tinents was in all probability not so great as at present. Yet, 

 M. Brongniart, for this reason, gives to the character of the 

 vegetation of this second and third period the name of a Coast 

 Flora. 



Before we conclude our remarks on a subject of such univer- 

 sal interest, we cannot help casting a look at the division of 

 plants into families, which, according to the investigations of M. 

 Brongniart, constitute the vegetation of his particular periods. In- 



