The Ferns of Washington 



49 



1. Cryptogramma acrostichoides R. Br. (PI. 17, 



f. 9, 10, 11.) 

 Leaves light-green; blades 2-3-pinnate; sterile blades 

 ovate to ovate-lanceolate, decidedly leaf-like, blade 

 1^ inches long; leaflets of sterile leaves ovate, twice as 

 long as wide, toothed or incised; leaflets of fertile leaves 

 crowded, narrowly elliptical, 3-6 times as long as wide. 

 Sori confluent at maturity, covering back of fertile 

 leaflets.-Alaska to Great Lakes, Colorado and Call- 

 lornia. 



2. Cryptogramma densa (Brack.) Diels. (PI. 17' 



f. 12 13.) 



(Pellaea densa Hook.) . 



Petioles wiry, 3-9 inches long, blades closely 3-pm- 

 nate, 1-2 inches long, ovate, coriaceous; segments 



linear, %-% inch long, nearly sessile, pointed 



or 



mucronate; fertile segments entire, margin recurved, 

 bearing a membranous indusium on ^J^j^ 

 ments sharply serrate, 

 and California. 



14. ADIANTUM. Maiden-hair Fern. 

 Petioles black or dark brown, shining; leaflets with 

 chief vein at lower margin, or none (ours) bo 

 ginal, borne on the under side of the inrolled eaf mar 

 gin on the tips of free forking veins, <*««JJ'£ d 

 -not, diatno-to moisten; because the 1 ; ues 

 water without getting wet.) Some imes go *n * 

 house plant, We have only the following species. ^ 



1. ADIANT, M PEDAT1M ALEUTICTJM Rupi- (W- J > 



f. 1, 2.) 



Maidenhair Fern. 



Blades smooth, thin, nearly circular f ^^ 

 inches in diameter: petioles long, grace , 

 times 2-forked, with the leaflets arising from the u P P 







