xxi] 



CYATHEACEAE 



373 



arborescent species of the genus have retreated to more southern 

 regions. 



Fio. 276. Oncopteris Nettvalli. (After Velenovsky ; | nat. size.) 



Fig. 277. Protopteris punctata. (After Heer ; very slightly reduced.) 



Protopteris punctata (Sternb.). Fig. 277. 



The earb'est information in regard to the anatomy of this 

 widely spread Lower Cretaceous fern we owe to Corda, who 

 showed that the species agrees in essentials with existing 



