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On the Fossil Flora. 



The fact that we do not know more than a few hundred species 

 of fossil plants, shews the impossibility of our pretending at 

 present to form any very plausible estimate or conception of the 

 nature of the antediluvian flora, and also the hazard of attempt- 

 ing, from the disappearance of a few species, in proceeding from 

 one formation to another, to determine the abundance or pau- 

 city of families or classes of plants. It is surprising to ob- 

 serve naturalists characterising botanically whole antediluvian 

 epochs, when they possess, as in the case, for example, of the 

 second epoch, the period of formation of the new red sandstone, 

 a group of twenty miserable remains, as the whole of the dis- 

 posable riches from which such a result is obtained. It is evi- 

 dent also that we cannot, from the present fossil vegetable re- 

 mains of single families, form any satisfactory inference as to the 

 number of their species, because it may have depended in part 

 on accident, or some unknown circumstances, that in one family 

 many species and individuals are preserved, while in another 

 but few remains are met with. In other cases the circumstances, 

 although easily understood, are not attended to, and the num- 

 ber of fossil species found in the deposit, are considered as the 

 full measure of what has been destroyed. Thus in the first 

 epoch two mosses only, but sixty-four lycopodiae, are enume- 

 rated ; but this circumstance does not prove that mosses and 

 lycopodiae formerly existed in the proportion of 2 to 64 ; for it 

 is very natural that gigantic lycopodium stems would more easily 

 resist the storms of time than the dwarf moss ; and although we 

 on that account have only two mosses remaining from that pe- 

 riod, it does not follow that they have not been more than ten 

 times more numerous than the lycopodia. 



It is doubtful if botanists can determine with accuracy evea 

 the family of the fossil species. Many of the remains at present 

 considered as Lycopodiums, may prove to be Ferns, or even 

 Pines, the Selaginites excepted. Many of the gigantic, so called 

 Equiseta, resemble tree-like grasses. The Marsileaceae of the 

 former world may have belonged to the ferns. The Voltzia 

 has not yet been proved to belong to the Coniferae, and as the 



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