go OUR NATIVE FERNS AXD THEIR ALLIES. 



3. A. Jordan! C. Muell. Stipes rather stout, nearly black, 

 polished; fronds ovate or deltoid-pyramidal, bi tripinnate; 

 pinnules and upper pinnae ample, smooth, or nearly so, rounded 

 or even reniform, upper margin rounded, slightly incised ; sori 

 2 5; transversely linear-oblong, subcontinuous. (A. emargina- 

 tum of former edition not Hook.) 



ft Fronds pilose, with whitish hairs. 



4. A. tricholepis Fee. Stipes smooth, polished, deep 

 black ; fronds oval ; pinnules roundish, moderately long-stalked ; 

 sori few (3 7), of unequal size; indusia very velvety. (A. 

 dilatatum Nutt.) Western Texas. 



** Fronds dichotomously forked,with numerous pinniz spring- 

 ing from the upper side of the two branches. 



5. A. pedatum L. Stipes 9' 15' long, dark chestnut- 

 brown, glabrous; fronds nearly circular in outline; central pin- 

 nee 6' 9' long, i' 2' broad; pinnules triangular-oblong, short- 

 stalked ; sori roundish or transversely oblong. North Carolina 

 to California and northward. 



Vctr. rangiferinum Burgess. Pinnules longer-stalked and 

 deeply cleft into narrow-toothed lobes on the upper side. Mount 

 Findlayson, British Columbia. 



XI. PTERIS L. BRAKE. 



Sori marginal, linear, continuous, occupying a slender fili- 

 form receptacle which connects the tips of the free veins. In- 

 dusium membranous, formed of the reflexed margin of the 

 frond. Name from Gr. itTspiS, a fern, from Ttrepov, a wing, al- 

 luding to the prevalence of pinnate fronds. A cosmopolitan 

 genus containing sixty or mo're species as now limited. 

 * Lower pinna linear, undivided. 



i. P. longifolia L. Stipes 6' 12' long, clothed more or less 

 below with pale-brown scales; fronds i 2 long, 4' 9' broad, 

 oblong-lanceolate; pinnae sessile, 2" 5" broad, linear, entire; 

 veins close and fine, usually once branched ; indusium yellowish 

 brown. Florida. 



* * Louver pinnce forked or slightly pinnate below. 

 2. p. Cretica L. Stipes 6' 12' long, erect, stramineous 

 or pale-brown ; fronds 6' 12' long, 4' 8' broad, lateral pinnae 



