have successively occupied the surface of the Earth. 357 



aumerous fossil vegetables still undescribed, and of which I shall 

 here notice the most remarkable. At the same time it should 

 be observed, that these plants are very peculiar, and probably 

 belong to a special flora, unless these differences depend upon a 

 diversity of station. 



Besides the different members of the eocene properly so called, 

 of the Paris basin, I include in this flora the fossils of the same 

 formation in England, in the Isle of Wight and the Isle of Shep- 

 pey, in the London basin. These last fossils, consisting almost 

 entirely of fruits transformed into pyrites, constitute a collection 

 which has no analogue at other points of the tertiary basins of 

 Europe, not merely on account of the number and diversity of 

 these fruits, but of the wholly special characters, which remove 

 them far from the plants of which the leaves are found in the 

 other strata of the same geological epoch. Everything therefore 

 leads us to think that these fruits, although belonging to plants 

 contemporaneous with the eocene deposits of Europe, have been 

 brought from distant countries by marine currents, as fruits are 

 still brought from the equatorial regions of America on to the 

 coasts of Ireland or Norway by the great current of the Atlantic. 

 The deposit of the Isle of Sheppey therefore appears an acci- 

 dental case in the eocene deposits, and the Paris basin does not 

 present any of these fossils. 



The tertiary basin of Belgium, which follows that of London, 

 has presented, near Brussels, some fossil fruits, very few in num- 

 ber, but apparently identical with one of the genera most abun- 

 dant in Sheppey. These are the Nipadites, at first regarded as a 

 species of Cocos, under the name of Cocas Burtini. 



Lastly, by the advice of my learned colleague M. Elie de Beau- 

 mont, I have included in this same flora the plants contained in 

 the lignites of the shores of the Baltic and of Pomerania, so rich 

 in amber, in which the plants have frequently been preserved. 

 To M. Goppert is owing our acquaintance with these plants, 

 represented most frequently by very small fragments, the rela- 

 tions of which he has determined with much sagacity and exac- 

 titude. 



With the materials collected from these various localities, but 

 most of which are still unpublished, we shall be able to construct 

 the flora of the eocene epoch, of which the following list, com- 

 prising only the species described or at least determined, is but 

 a sketch. 



Flora of the Eocfene Epoch, 



Amphigenous Cryptogams. 

 Alg^. 

 Confervites thorseformis, Brong. 

 Bolca. 



Caulerpites Agardhiana, Brong. — 

 Bolca. 



pinnatifida, Brong. — Bolca. 



Zonantes flabellaris, Sternb. — Bolca. 



