48 American Fern Journal 



est, veins free. Sori usually continuous on terminal 

 veins, marginal; indusium formed from reflexed margin 

 of leaf, roundish. (Greek cheilos = margin, anthos = 

 flower; because the sori are marginal.) 



A. Leaves 2-pinnate, lower surface densely covered with short hairs. 



1. C. gracillima. 



AA. Leaves 3-pinnate, lower surface covered with long woolly hairs. 



2. C. feet. 



1. Chellanthes gracillima Eat. (PI. 17, f. 5, 6.) 



Lace Fern. 



Petioles 2-5 inches long, brown, shining, slightly 

 hairy; leaf-blades lanceolate, 2-pinnate, 1-4 inches long; 

 leaflets entire; under surface densely covered with short 

 brown hairs. — British Columbia to Idaho and Cali- 

 fornia. 



2. Cheilanthes Feei Moore. (PI. 17, f. 7, 8.) 



Petioles 1-3 inches long, dark-brown, shiny, more or 

 less hairy; leaf-blades ovate to lanceolate, 3-pinnate, 

 1-3 inches long, under surface densely covered with 

 long woolly brown hairs.— British Columbia to Illinois, 

 south to Arizona and Texas. 



13. CRYPTOGRAMMA. Rock Brake. 



Plants low. Leaves tufted, smooth, 2-3-pinnate, the 

 fertile somewhat unlike the sterile ; petioles of the fertile 

 ones longer than those of the sterile, and the leaf- 

 divisions much narrower. Sori roundish or oblong, at 

 or near the ends of free veins, covered by reflexed leaf- 

 margin when young but almost free when mature. 

 (Greek cryptos= hidden, grammar & line; because the 

 line of sporangia is at first hidden by the leaf-margin.) 



A. Sterile leaflets obtuse, ovate-oblong; indusium not scarious. 



l.C. acrostic hoides. 

 A A. Stenle leaflets very acute, linear-lanceolate; indusium scarious. 



2. C. densa. 



