Cn. XXIIL] 



PEEMIAN FLOEA. 



857 



Fig. 463. 



(see fig. 463), supposed by A. Brongniart to be allied to Cycas^ is another 



link between the Permian and Carboniferous vegetation. Coniferse, of 



the Araucarian division, also occur ; but these are 



likewise met with both in older and newer rocks. 



The plants called Sigillaria and Stigmaria^ so 



marked a feature in the carboniferous period, are 



as yet wanting. 



Among the remarkable fossils of the rothlie- 

 gendes, or lowest part of the Permian in Saxony 

 and Bohemia, are the silicified trunks of tree-ferns 

 called generically Psaronius. Their bark was 

 surrounded by a dense mass of air-roots, which 

 often constituted a great edition to the original 

 stem, so as to double or quadruple its diameter. 

 The same remark holds good in regard to certain 

 living extra-tropical arborescent ferns, particularly 

 those of New Zealand. 



Psaronites are also found in the uppermost coal 

 of Autun in France, and in the upper coal-meas- 

 ures of the State of Ohio in the United States, but 

 specifically different from those of the rothlie- 

 gendes. They serve to connect the Permian flora 

 with the more modern portion of the preceding or 

 carboniferous group. Upon the whole, it is evident that the Permian 

 plants approach much nearer to the carboniferous flora than to the tri- 

 assic ; and the same may be said of the Permian fauna. 



J^oeggerathia cuneifoUa. 

 Ad. Brongniart* 



* Murchison's Eussia, vol. ii. pi. A, fig. 3. 



