FILIOKS. 4i.> 



13. OSMUNDA, Linn. Flowering Fern. 



Omunder, a Saxon name of Thor, a celtic divinity. 



Sporangia globose, short-pedicelled. naked, entirely cov- 

 ering the fertile fronds or pinuae (which are contracted to the 

 mere rachis,) thin and reticulated, not striate-rayed at the 

 apex, opening by a slit into 2 valves across the apparent top 

 Spores green. — Fronds tall and upright, from thickened root- 

 stocks, 1 to 2-j) innate ; the veins forking and free. 



1. 0. CLAYTONIANA, L. Clayton's Flowering Fern. 



Frond pinnate, 16 to 24 inches long, linear-oblong in outline; pinnx mostly 

 opposite piunaund, 2 or 3 of the central pairs contracted into pinnate clusters of 

 dark brown spore-cases. 



Low wet grounds, common. June. 



%. 0. SPECTABILIS, Willd, Show?/ Flowering Fern. 



Very smooth, pale, 2 to 4 feet high; sterile pinnules 20 or more, ia^ce-oblong, 

 rather oblique but not auricled al the base, 2 incites long; the ferule forming an 

 oblong racemose paniele at the summit of the fronds. 



Swamps, common. July. 



2. 0. CINNAMOMEA, L. Cinnamon Fern. 



Sterile frond pinnate; smooth when full grown; pinna: elongated, pinnatifid; 

 segments ovate-obloug, entire; fertile frond bipiuaate, usually central less nu- 

 merous than the sterile, with the pinnae much smaller, aud covered with dense 

 Blusters of cinnamon-colored spore-cases'. 



Swamps anl low places, vey common. May. — Growing in large bunchei, 2 to-3 

 feet high, at length 4 or 5 feet, 



14. BOTRICHIUM, Swarts. Moonwort. 



Gr. tortus, a cluster of grapes, from the appearance of the fruitful fronds. 



Spore-cases subglobose, 1-celled, 2-valved, distinct, 

 smooth, sessile along the margin of a compound pinnate ra- 

 chis, opening transversely. Indusium none. SPORANGH 

 ecssile, clustered but distinct. 



B. Yirginicum, Swarts. Virginian Moonwort. 



Somewhat hairy, 10 to 20 inches high ; sterile frond above the middle, fcro*dly 

 triangular is outline, spreading, 6 to 12 inches wide, ternately divided to the base, 

 sessile, thin ; the branches pinnate ; piancn pmnately parted ; pinnules lane* oblong, 

 cut pinnatifid or sharply toothed; frustijicuiion 2-phinate. 



llich woods, common. July. 



Sub-order III. OPHIOGLOSSE^. 



Sporangia spiked, closely sessile, not reticulated, opening 

 by a transverse slit. — Fronds straight , never rolled in the hm( 



15. OPHIOGL0SSUM, Linn. Adder's-tongue. 



Gr. opkis, a serpent, and glossa, tonge. 



-Spore-cases roundish, smooth, closely packed in 2 rank* 



