120 OUR NATIVE FERNS AND THEIR ALLIES. 



fiat from an early stage, concealed under the sorus, its margin 

 cleft into slender hairs or cilia. 



* Stipes obscurely jointed near the base ; cilia of the indusiuin 

 long, inflexed over the sporangia. 



t Fronds thickly clothed underneath with rusty bristle-like 

 chaff. 



I- W. Ilvensis R. Br. Fronds broadly lanceolate, smooth- 

 ish above, pinnate ; pinnae crowded, sessile, pin nately- parted, 

 the crowded segments oblong, obscurely crenate ; sori near the 

 margin, somewhat confluent when old. ( W. rufidula Beck., 

 Acrostichum license L., PoJy podium Ilvensc Swz., Nephrodinm 

 rufiduliim Michx., Aspidium rufiduliim Willd.) Virginia to 

 Kentucky, westward and northward. 



ft Fronds glabrous or nearly so. 



$023 "~ 2 - W. hyperborea R. Br. Stipes and rachis sometimes 

 slightly hairy ; fronds linear-lanceolate, pinnate ; pinnae corda- 

 to-ovate, pinnaiifid with few (5 7) broadly obovate entire lobes. 

 Vermont, New York, and northwestward. 



M22 3- w< # Iabella R. Br. Smooth and naked throughout; 

 fronds linear, tapering slightly below, 2' 5' high, pinnate; 

 pinnae deltoid or ovate, the lower rather remote, cut into 3 7 

 rounded or subcuneate entire lobes. Vermont, New York, and 

 northward. 



** Stipes not jointed ; cilia of the indiisium very short, hid- 

 den by the sporangia. 



302& - 4- W. scopulina D. C. Eaton. Rootstock short, creep- 

 ing, very chaffy ; stipes 2' 4' long, puberulent like the rachis 

 and under surface of the frond with minute flattened hairs and 

 stalked glands; fronds lanceolate, 4' 8' long, pinnate; pinnae 

 numerous, oblong-ovate, pinnatifid with 10 16 short ovate or 

 oblong toothed divisions ; indusia very delicate, deeply cleft 

 into laciniae which terminate in short hairs. Colorado, Ari- 

 zona, California, Oregon, and northward. 



5- w - Oregana D.C.Eaton. Stipes and fronds smooth; 

 fertile fronds taller than the sterile ones; pinnae triangular-ob- 

 long, pinnatifid ; segments oblong or ovate, toothed or crenate; 

 teeth often reflexed and covering the submarginal sori ; indusia 



