The Ferns of Washington 53 



A. Leaf-blade leathery, broadly ovate; margin of leaf-segments bluntly 



serrate. »■ P - ScoukrL 



AA. Leaf-blade membranous, linear to oblong. 



B. Leaflets or leaf-divisions acute or acuminate, their margin sharp y 



serrate. 2 - R 0CCldentale - 



BB. Leaflets or leaf-divisions obtuse, their margin entire. 



3. P. hesperium. 



1. Polypodium Scouleri Hook. & Grev. (PL 20, 



f. 1, 2.) 



Leather-leaf Polypod. 



Leaf-blade leathery, broadly ovate, 3-12 inches 

 long; leaf-segments linear to oblong, obtuse, the teeth 

 rounded. Sori on upper leafsVegments — Near sea-water. 

 British Columbia to California. 



2. Polypodium occidentale (Hook.) Max. (PI. 20, 



f. 5, 6.) 



Licorice Fern . 



Rootstock yellowish. Leaves 6-18 inches long; blade 

 1^-4 inches wide, oblong to linear, acuminate, mem- 

 branous; leaf-segments numerous, tapering from a mae 

 base to an acute or acuminate tip, sharply serrate, 

 veins free, with 2-4 veinlets. Sori near nud-vera. 

 On rocks, logs and tree trunks. Alaska to California 

 and along the coast.-The rootstocks have a strong 

 licorice taste and are often collected by children tor 



■ & 



chewing. 



3. Polypodium hesperium Max. (PL 20, I 3, 



Leaves membranous, 2-6 incites long; blade HH H 

 inches wide, linear to oblong, obtuse to acute; leal-, g- 

 ments short, rounded at tip, crenulate to entire, venu 

 free, 1-2-forked. Sori large, midway between mid 

 vein and edge.-On dry rocky hillside*. British Col 

 umbia to Montana and Arizona. 



