634 FILICES. (FERNS.) 



minate, pinnatifid, 3' -4' long, the segments entire; veins simple. (Poly- 

 podium, L.) Rocky woods, East Florida (Miss Reynolds). 



4. P. reptans, D. C. Eaton. Fronds spreading or procumbent, often 

 rooting at the apex, l-2 long; pinna; '-!' long, oblong, obtuse, crenate, 

 truncate at the base, short-petioled, the lower distant ; veins branching. (Poly- 

 podium, Swartz.) Heruando County, Florida ( J. D. Smith). 



19. ONOCLEA, L. 



Fertile fronds contracted, the pinnules strongly revolute and berry-like ; 

 fruit-dots on the back of the free veins, with an elevated receptacle ; indusium 

 attached partly to the receptacle and partly to the interveuular surface. 

 Sterile fronds foliaceous, much taller than the fertile one_s. 



1. O. sensibilis, L. Sterile fronds on a long smooth stipe, broadly 

 deltoid-ovate, pinnatifid almost or quite to the rachis ; the divisions lanceo- 

 late, entire or crenately incised ; veins finely reticulated with oblong-hex- 

 agonal areoles ; fertile fronds shorter, bipinnate ; pinna; erect, appressed to 

 the rachis; the pinnules crowded. Meadows and wet places. Ilootstock 

 nearly naked, creeping. Fronds varying from four inches to three feet in 

 height. 



20. WOODSIA, R. Br. 



Fruit-dots on the back of the veins ; the involucres placed beneath the 

 fruit-dot, saucer-shaped or cup-shaped, divided into irregular lobes or a deli- 

 cate fringe, or sub-globose and contracted at the mouth. Small Ferns with 

 many fronds from a short scaly rootstock. 



* Involucre fringed, the hair-like divisions incurved on the sporangia 



1. W. Ilvensis, R. Br. Fronds sparingly hairy above, villous beneath 

 and on the stipe and rachis with brown hairs and narrow chaff, lanceolate, 

 pinnate ; pinnas ovate-oblong, deeply pinnatifid, the divisions oblong, obtuse, 

 entire or crenate. Fruit-dots enveloped in the fringe of the involucre. 

 Rocks along the Alleghany Mountains. Fronds 3' - 8' high. 



* * Involucre divided into a few irregular lobes. 



2. "W. obtusa, Torr. Fronds nearly smooth, broadly lanceolate, pinnate, 

 or near the rachis bipinnate ; pinnre triangular-ovate, the lower ones distant, 

 pinnately parted ; segments oblong, obtuse, the upper ones toothed, the lower 

 ones pinnatifid with toothed lobes ; veins forked, the tips whitish on the upper 

 surface of the frond ; fruit-dots on the lobules; involucre delicate, the lobes 

 hidden by the ripened sporangia. Rocky places, Georgia, and northward. 

 Fronds 6' -16' high. 



21. DICKSONIA, L'Her. SITOLOBIUM, Desv. 



Fruit-dots small, globular, terminal on the free veins ; sporangia on an ele- 

 vated receptacle in a thin cup-shaped involucre which is partly adherent to a 

 reflexed lobule of the frond. Fronds large, 2-3-pinnafe, from a creeping 

 rootstock. DICKSOXIA proper has large two-lipped involucres, of a firmer 

 texture, and several species have an arborescent caudex. 



