CRYPTOGAMIA JFIL1CES 575 



front,— naked, or covered with an Indusium or veil,— with or without an clastic 

 ring. Plants xcilh a horizontal rhizoina, unit leaf-like fronds, whi<h are simple, or 

 variously divided. Vernation circinate. Xat. Ord- 2C>4. Limit. 



Sect. 1. Capsules l-cellcd, furnished xvith an articulated elastic 

 end usually incomplete ring, bursting transversely arid irregular! n. 

 Poltpodiack.*. Lindl. 



460. POLYPODIUM. L. Mtft. Gen. 786. 

 [Greek, Polys, many, and Pous, poilos, foot ; frum its numerous roots.] 



Sori roundish, scattered on various parts of the under surface of the 

 frond. Indusium none. 



f Frond pinnatifid. 



1. P. rcLOARK, L. Frond deeply pinnatifid, smooth ; segments linear- 

 •btong, obtuse, crenate-serrulate, the upper ones gradually smaller; sori 

 large, distinct Beck, Bot. p. 447. 



P. virginianum. Muhl. Catal. p. 97. Also, Willd. Sp. 5. p. 174. 

 Pursh, Am. 2. p. 658. JVutt. Gen. 2. p. 250. Bart. Phil. 2. p. 207. 

 Common- Polt podium. 



Rhizoma creeping, clothed with membranaceous tawny scales. Fronds 4 to S 

 •r 10 inches long, and an inch and half to 9 inches wide, oblong-lanceolate, pin- 

 nately divided nearly to the midrib ; segment* mostly alternate, sometimes nearlr 

 or quite opposite, 1 fourth to 1 third of an inch wide, linear-oblong, obtuse, slight- 

 ly serrate or crenate ; stipe or petiole naked and smooth (chaffy, Willd. Pursh). 

 flatlish or somewhat channelled on the upper side, obscurely and obtusely mai- 

 tined by the decurrence of the frond. Sori large, in 2 rows on the back of each 

 segment, distinct, or finally in contact,-prescnting dense circular clusters of 

 small naked tawny or ferruginous grains. 



Hub. Rocky woodlands : frequent. />. July. 



Obs. This is the P. virginianum, Muhl Willd. See and seems to differ from P. 

 xulgare, of Europe, in nothing but its naked stipe. 



f f Frond bipinnatifd. % 



1 P. HMAGOirt>PTEiiUM, Mr. Frond bipinnatifid, slightly pubescent 

 and ciliate ; divisions lanceolate, the lower pairs adnate-decurrent, 

 connected by an oblong hexagonal wing ; segments lance-oblong, rather 

 obtuse, the lower ones crenately incised, the upper ones entire; sori 

 minute. Beck, Bot. p. 447. 



HKXAOONAL-WiyGED PoLTPODIUM. 



Fronds 6 to 9 inches long, and, at base, nearly as wide as long, forming in their 

 outline almost an equilateral triangle, somewhat pubescent, especially on the 

 midrib, bipinnatifid, the divisions lanceolate, pinnatifid, a few of the lower pain 

 united by an oblong and somewhat hexagonal wing on the midrib, one or both o f 

 the lowest pair often deflexed ; stipe 8 to 12 or 15 inches long, slender, naked. 

 Sori very small, roundish, distinct, somewhat in 2 rows, but often irrregaiar, on 

 the back of the segments. 



Hob. Moist woodlands : frequent. Ft. July. 



Obs. Four or five additional species are enumerated in the V. States. 



