FILICES. / 



die one slightly stalked, rhomboid-ovate, pinnatifid into a few 

 toothed segments, the second pair larger than the first ; the 

 side divisions sessile, deltoid, pinnatifid on upper side as in 

 middle division, but each bearing on the lower side a single 

 large pinnatifid basal segment, and above it smaller segments 

 like those of the upper side; lower surface covered with pale- 

 yellow powder. (N. cretacea of check-lists not of Liebm., N. 

 Candida, var. ^-fido-palmato Hook.) Texas to Arizona. 

 ft Fronds lanceolate or linear-oblong, bipinnate or tripinnatifid. 



9. N. Grayi Dav. Stipes tufted, ij' 3^' long, terete, 

 chestnut-brown, with nearly black, rigid, linear-acuminate 

 scales below, paler, deciduous scales above ; fronds 2' 4' long, 

 f ij' broad, oblong-lanceolate, once or twice pinnate, upper 

 surface sparingly, under thickly covered with white powder; 

 rachises brown like the stipes, coated with a granular substance 

 extending down the stipes, and clothed with long, slender, en- 

 tire or ciliate, pale or whitish scales ; pinnae short-stalked, 

 oblique, unequally triangular-ovate, ovate-lanceolate, or lanceo- 

 late, deeply pinnatifid or pinnately divided into i or 2 pairs of 

 short-stalked or sessile, oblong, pinnatifid, obtuse pinnules, the 

 remaining portion obliquely pinnatifid with alternate, lobed or 

 entire segments ; margins unchanged, reflexed ; sori brown in 

 a continuous line at the ends of the free veins. Southeastern 

 Arizona. 



10. N. Lemmoni D. C. Eaton. Rootstock short, scaly 

 with narrow, pointed, rigid, dark-brown chaff; stalks dark red- 

 dish-brown, wiry, 4' 6' long, chaffy at the base with scales a 

 little wider and more scarious margined than those of the root- 

 stalk, otherwise smooth ; fronds 6' 9' long, i' 1' wide, linear- 

 oblong, pinnate with numerous deltoid or ovate, once or twice 

 pinnatifid pinnae, the lowest ones a little shorter than the mid- 

 dle ones ; upper surface herbaceous-green, smooth ; lower sur- 

 face covered with white or slightly yellowish ceraceous powder ; 

 sori forming a narrow sub-marginal line; margins of the seg- 

 ments very slightly recurved. Arizona. 



ttt Fronds deltoid-ovate, tri quadripinnate at base. 



ir. N. nivea Desv. Rootstock short, chaffy with narrow 

 scales ; stipes tufted, 4' 6' long, wiry, black and polished ; 



