364 M. Brongniart on the different Floras which 



cold regions. The presence of equatorial forms, especially of 

 Palms, appears to me to distinguish this essentially from the 

 following epoch. Finally, the very small number of plants with 

 a monopetalous corolla will be remarked, confined to species re- 

 ferred by Unger to the Apocynese, and the genus Steinhauera 

 founded on a fruit which is closely related to that of the Morinda 

 among the Rubiacese. 



3. Pliocene Epoch. 



This epoch, embracing all the tertiary beds superior to the 

 shell-marls of Touraine, comprehends a considerable number of 

 localities, rich in fossil plants, and which have their position 

 determined as much even by the ensemble of the vegetation they 

 contain as by their other geological characters. The tertiary 

 basins which it appears to me should form the basis of this 

 flora, both from their identity and the numerous well-studied 

 plants they contain, are : — That of CEningen near Schaff hausen 

 (CEn.), the species of which were long ago studied and determined 

 by M. Alex. Braun, whose labours, although unpublished, have 

 been communicated to several scientific men, in particular to M. 

 Unger; that of Parschlug in Styria (Parschl.), the numerous 

 impressions of which have been combined, studied and deter- 

 mined by M. Unger, published in part in his ' Chloris protogsea,^ 

 and presented as a whole in a special enumeration of these species 

 lately pubhshed under the title of ' Flora of Parschlug.' In this 

 locality alone M. Unger has recognized and classed 110 different 

 species ; it is the most numerous local fossil flora known, and the 

 identity of a great number of species with those of CEningen in- 

 dicates the synchronism of these two local formations. Some 

 other points in Styria also seem to be of the same epoch, as well 

 as several localities in Hungary, very rich in silicifi.ed wood. In 

 Bohemia the tripoli schists of Bilin and Comothau, which con- 

 tain a rather large number of plants, described by M. Sternberg, 

 are doubtless referable to this epoch, from the nature of the 

 plants ; lastly, the tertiary hills, called the subapennine hills of 

 the Placentian district, of Tuscany and a portion of Piedmont, 

 as well as the gypseous formation of Stradella, near Pavia, so 

 rich in impressions of leaves, form part of this epoch ; but, with 

 the exception of this last point, these beds generally contain but 

 few plants. 



In France the pliocene epoch probably comprehends a portion 

 of the freshwater deposits of Auvergne and Ardeche. Thus the 

 schists of Menat and those of Rochesauve appear to me to pre- 

 sent a flora very analogous to that of CEningen and of Parschlug. 

 As to the marls of Gergovia and Merdognc near Clermont, I 

 have considered it best to class them rather in the miocene epoch ; 



