Postelsia 2 
“I 
i 
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 solidungula. 
Lamina not ligulate, oblong, entire, cuneate at 
base, variable, not more than 1o centimeters wide, 
and 50 centimeters long, no mucilage ducts; 
sori very variable in shape and size, yellow- 
brown, of delicate texture. Renjrewia parvula. 
Texture and anatomy like the above but 
much longer, to 40 times as long as wide, 
tapering more gradually to the base. 
Renjrewia parvula perlonga 
Lamina suborbicular, digitately divided, 125 
centimeters long. Renjrewia yezzensis. 
EXPLANATION OF PLATES 
Plate XVI. 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 lamine are 
sterile; the darker patches are sori on one side 
