FILICES, 87 



die one sliglitly stalked, pinnaiifid into a few toothed segments, 

 the second pair hirger than the first; side divisions bearing a 

 single large pinnatifid basal segment on the lower side, and 

 above it smaller ones like those of the upper side ; lower surface 

 covered with pale, yellow powder. Texas to Arizona. 



ft Fronds lattceolate or linear-oblojig, bipinnatc or tripinnattfid. 



9. N. Grayi Dav. Stipes tufted, i' — 4' long, chestnut-brown, 

 with nearly black, rigid scales below, paler deciduous scales 

 above; fronds 2' — -6' long, J' — ij' wide, the upper surface spar- 

 ingly, the lower thickly, covered with white powder; pinnae 

 short-stalked, unequally triangular-ovate, deeply pinnatifid or 

 divided into one or two pairs of oblong pinnatifid, obtuse pin- 

 nules, the remaining portion obliquely pinnatifid with alternate 

 segments; sori brown. Southeastern Arizona to Texas. 



10. N. Schaffneri (Fourn.) Unde. Rootstock short, stout, 

 with black pectinate scales; stipes i' — 2' long, brownish-black, 

 with narrow, rigid scales ; fronds lanceolate, 5' — 8' long, bi — 

 tripinnatifid, the pinnules numerous, narrow, with narrow dark 

 scales underneath; sori continuous, brown or black. {N.Neal- 

 leyl Seaton, Aleuritoptcris Schaffiwri Fourn.) Western Texas 

 {Nealhy). 



1 1. N. Lemmoni D. C. Eaton. Rootstock short, scaly, with 

 narrow, rigid, dark-brown chaff; stalks reddish-brown, 4' — 6' 

 long, chaffy only at base with wider scarious-margined scales; 

 fronds 6' — 9' long, i' — lA' wide, with numerous deltoid or ovale 

 pinnae, the lowest a little shorter than the middle ones; upper 

 surface smooth, the lower with white or yellowish powder; sori 

 in a narrow submarginal line. Arizona. 



ttt Fronds deltoid-o%'ate, Iri — quadrtpinnate at base. 



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

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



