FILICE8. 



395 



2 5. AspmiEAE : Sori mostly orbicular, rarely ollwg, and then placed across tl* 

 vein; im.lu.-ium orbicular, reniform, or hooded. 



a. Yeins all free, none, reticulated. 

 M- Indusium inflated, fixed by half, or all, the margin. 



518. WOODS'IA, R. Brown. 

 [Dedicated to Joseph Woods; an English Botanist.] 



Sori globular, borne on the back of simply forked veins ; indusium 

 thin, attached all round the receptacle, open, or early bursting, at 

 the top, or centre,-^-thQ orifice jagged,, and often fringed with hairs 

 which involve the sporanges. 



f Indusium soon spreading open, larger than the, sorus, and appearing as if placed 

 under it,jagged-lobed, but not fringed with hairs. 



1. W. obt lisa, Torrey. Fronds sub-bipinnate, glandular-hairy ; 

 pinnae rather remote ; pinnules oblong, very obtuse, crenately 

 pinnatifid. 



W. Perriniana. Hook $ Grev. $ FL Cestr. ed. 2. p. 580. 

 OBTUSE WOODSIA. 



Fronds 3 to 6 or 8 inches long, and 1 to 2 or 3 inches wide, lance-oblong in their 

 outline ; pinnae % an inch to 1% inches long, subsessile ; common rachis slightly 

 chaffy above ; stipe 2 to 3 inches long, chaffy. Sori near the margin of the lobes, 

 finally almost confluent; indusium sub-hemispherical, at length resembling a 

 calyx, with small spreading denticulate segments. 

 Hab. Rocky banks ; along streams : frequent. Fr. July. 



f t Indusium minute, soon opening flat, and concealed under the sorus, except itt 

 marginal fringe. 



2, W. 11 veil sis, R. Br. Fronds pinnate, thickly clothed beneath 

 with russet bristle-like chaff; pinnae crowded, deeply pinnatifid, 

 the lobes obscurely crenate. 



ELBA WOODSIA. 



Fronds 2 to 4 inches long, and about an inch wide, oblong-lanceolate in their 

 outline ; pinnae % to % of an inch long, subsessile ; common rachis chaffy ; stipe 

 1 to 3 or 4 inches long, chaffy, with a tuft of tawny chaff at base. Sori finally 

 confluent ; sporanges slightly pedicellate. 



Hab. Rocky banks of streams; Schuylkill : not common. Fr. July. 

 - *+ Indusium flat, reniform, or orbicular and umbtticate, opening round the whoh 

 margin. 



519. DRYOP'TERIS, Adanson. 



[Gr. Drys, an oak, and Pteris, a fern ; from their growing usually in woods.] 

 Sori roundish, borne on the back, or near the apex, of the simple 

 and free pinnate veins, or their forks. Indusium flattish, roundish- 

 reniform, fixed at the sinus, opening round the margin. Fronds 

 thinnish, simply, or bi- tri- pinnate. 



f Veins simple and straight, or simply forlced; stipes nearly naJ<ed; fronds pinnate. 



1. D. Thelyp'terls, A. Gray. Fronds lanceolate ; pinnae linear- 

 lanceolate, deeply pinnatifid, the lobes nearly entire, withrevolute 

 margins; sori soon confluent. 



