IP s t e I s i a 271 



Renjrewia may be presented. Lamina ligulate 

 by the persistence of the lamina of the preceding 

 year, with a succession of oval sori, obovate, 

 up to 15 centimeters wide (at least), mucilage 

 ducts well developed. Renjrewia solidiingula. 

 Lamina not ligulate, oblong, entire, cuneate at 

 base, variable, not more than 10 centimeters wide, 

 and 50 centimeters long, no mucilage ducts; 

 sori very variable in shape and size, yellow- 

 brown, of delicate texture. Renjreivia parvula. 



Texture and anatomy like the above but 

 much longer, to 40 times as long as wide, 

 tapering more gradually to the base, 



Renjrewia farvnla ferlonga 



Lamina suborbicular, digitately divided, 125 

 centimeters long. Renjrewia yezzcensis. 



EXPLANATION OF PLATES 



Plate XVL A series of representative forms 

 of Renjrewia stretched on a glass plate and 

 photographed by transmitted light to show 

 the sori which are nearly invisible by reflected 

 light. The light portions of the laminae are 

 sterile; the darker patches are sori on one side 



