Pinna of barren Frond— under side. 



CYSTOPTERIS TENUIS. 



ScHOTT. J. Smith. Moore and Houlston 



PLATE XXXV. VOL. VIT, 



Aspidiwrn tenue, 



*' atomariunit 



Nephrodium tenue, 

 Cystopteris fragilis, var 



swartz. schkuhr. willdenow. 

 Muhlenberg. Willdenow. 



MiCHAUX. 



Hooker. 



Gystopteris — Bladder Fern. 



Tenuis — Slender. 



It would be difficult to find a Fern more appropriately 

 named than this species, the fronds are so slender and fragile 

 that they can scarcely bear their own weight, although the 

 substance of the frond is remarkably thin. Some authorities 

 consider it a variety of Cystopteris fragilis, but I think there 

 can hardly be a doubt as to the two being perfectly distinct 

 species. 



A half-hardy deciduous Fern. 



Native of North America. 



The fronds are sub-tripinnate, and oblong-lanceolate in form; 

 pinnules oblong and rather ovate, the one next the rachis 

 being largest; profoundly pinnatifid, with blunt dentate segments. 



