386 FILICALES [CH. 



a vertical or slightly oblique annulus and the rhizome is 

 similar to that of Dictyophyllum exile. The habit of the 

 genus is shown in fig. 284, which represents one of the 

 German Rhaetic species. 







-<§), 

 '""a^- 



Pig. 284. Thaumatopteris Miinsteri. (From a specimen in tlie Bergakademie, 

 Berlin ; ^ nat. size.) 



Clathropte^'is. 



Clathropteris meniscoides, Brongn. Fig. 285. 



Clathropteris, founded by Brongniart' for Rhaetic specimens 

 from Scania, agrees very closely with some species of Dictyo- 

 phyllum, but in view of the more rectangular form of the 

 venation-meshes it is convenient to retain both names. The 

 type-species was originally named Ftlicites nieniscuide.s^ and 

 afterwards transferred to Clatliropteris. An examination of 



^ Bronguiart (25). - Brongniart (25). 



