POLYPODIACEAE (FERN FAMILY) 19 



1. Phegopteris Dryopteris (L.) Fee, Gen. Fil. 243. 1850-52. Fronds 

 smooth and thin, 1-2 dm. wide and long, lateral divisions divergent, all tri- 

 angular and pinnate; the pinnae pinnatifid into oblong, obtuse, entire or even 

 pinnately lobed segments; lowest inferior pinna of the lateral divisions equal 

 to the second pinna of the middle division. Open rocky woods; reported 

 from Colorado; across the continent northward. 



3. POLYPODIUM L. POLYPODY 



Stipes articulated to the branching rootstocks. Leaves pinnate. Veins uni- 

 formly free. Sori large, round, on the veins or at their ends, without indusium. 



1. Polypodium hesperium Maxon, Proc. Biol. Soc. Wash. 13: 200. 1900. 

 Leaves subcoriaceous, 5-20 cm. long, ovate-oblong to oblong-linear, pinnatifid 

 into linear-oblong obtuse or acute segments, the lowest ones rarely diminished: 

 veins branched into three or four veinlets, the lowest ones on the Dipper side 

 of the vein bearing at their thickened ends the subglobose sori midway be- 

 tween the midrib and the margin of the segments. P. vulgar e. From the 

 Rocky Mountains eastward to the Atlantic; also westward. 



4. NOTHOLAENA R. Br. 



In ours the leaves are 3-5-pinnate, and covered beneath with a white or 

 yellow powder, the primary and secondary pinnae distinctly stalked, and the 

 ultimate pinnules very small, oval or 2-3-lobed. Sori somewhat elongated, 

 often of very few sporangia, situated below the tips of the veins near the 

 margin of the lobes of the fronds. 



1. Notholaena Fendleri Kunze, Farrnkr. 2: 87. 1851. Leaves densely 

 tufted, 5-15 cm. long, broadly deltoid ovate, 4-5-pinnate; the stipes dark 

 brown; rachis and all its branches flexuous and zigzag; the pinnae alternate; 

 ultimate pinnules 2-4 mm. long. In clefts of cliffs; Colorado to Arizona and 

 Texas. 



6. ADIANTUM L. MAIDENHAIR 



Stipe mostly blackened or very dark purple-brown, and commonly highly 

 polished. Sporangia borne at the ends of the veins, on the underside of the 

 reflexed margin of the frond. Midvein of the pinnules eccentric, dissolving in 

 the forking veinlets. 



Fronds bipinnate, ovate-lanceolate . . . . . . 1. A. capillus-veneris. 



Fronds dichotomous, orbicular in outline . . . . . 2. A. pedatum. 



1. Adiantum capillus-veneris L. Sp. PI. 1096. 1753. Fronds pyramidal, 

 with the rachis continuous to the terminal pinnule. 2-4 dm. long, often 

 pendent, ovate or ovate-lanceolate, 2-3-pinnate at base; pinnules wedge- 

 obovate or rhomboid, 1-2 cm. long, deeply and irregularly incised, smooth: 

 involucres lunulate or transversely oblong. In moist rocky places; southern 

 California across the continent to Virginia and Florida; rare if at all within 

 our range. 



2. Adiantum pedatum L. Sp. PI. 1095. 1753. Frond often 2-3 dm. broad: 

 stipe forked at the top, the branches recurved, and bearing several pinnate 

 divisions on the upper side; primary divisions 6-14, bearing numerous oblong 

 or triangular-oblong pinnules, which have the lower margin entire and the 

 upper more or less lobed: involucres oblong-lunate or transversely linear. 

 Across the continent and far northward ; within our immediate range reported 

 only from the Black Hills of Dakota, and from Utah. 



6. PTERIDIUM Scop. BRACKEN OR BRAKE 



In ours the rootstock is stout, cord-like, and extensively creeping. Fronds 

 scattered, ternate, with decompound divisions, and pale green stipe. Sporangia 



