46 OSMUNDACEAE (FLOWERING FERN FAMILY) 



simply linear, or (in foreign species) fan-shaped or dichotomously many-cleft 

 fronds (whence the name, from <rxl<, to split). 



1. S. pusilla Pursh. Sterile fronds linear, very slender, flattened and 

 tortuous ; the fertile ones equally slender (0.5 mm. wide), but taller (5-12 cm.) 

 and bearing at the top the fertile appendage consisting of about 5 pairs of 

 crowded pinnae (each 2-3 mm. long). Low grounds, pine barrens of N. J. ; 

 N. S. ; very local. Sept. (Nfd.) 



2. LYGdDIUM Sw. CLIMBING FERN 



Fronds twining or climbing, bearing stalked and variously lobed (or com- 

 pound) divisions in pairs, with mostly free veins ; the fructification on separate 

 contracted divisions or spike-like lobes, one side of which is covered with a 

 double row of imbricated hooded scale-like indusia, fixed by a broad base to 

 short oblique veinlets. Sporangia much as in Schizaea, but oblique, fixed 

 to the veinlet by the inner side next the base, one or rarely two covered by each 

 indusium. (Name from Xiryc^s, flexible.) 



1. L. palmatum (Bernh.) Sw. Very smooth ; stalk-like fronds slender, 

 flexile and twining (3-10 dm. long), from slender running rootstocks; the short 

 alternate branches or petioles 2-forked ; each fork bearing a round-heart- 

 shaped palmately 4-7 -lobed frondlet ; fertile frondlets above, contracted and 

 several times forked, forming a terminal panicle. Low moist thickets and open 

 woods, s. N. H. to Fla., Tenn., and Ky. ; local. Sept. 



OSMUNDACEAE (FLOWERING FERN FAMILY) 



Leafy plants (ours herbaceous), with creeping rhizomes. Sporangia naked, 

 globose, mostly pediceled, reticulated, with no ring or with mere traces of one near 

 the apex, opening into two valves by a longitudinal slit. Stipes winged at the 

 base. 



1. OSMUND A [Tourn.] L. FLOWERING FERN 



Fertile fronds or fertile portions of the frond destitute of chlorophyll, very 

 much contracted, and bearing on the margins of the narrow rhachis-like 

 divisions short-pediceled and naked sporangia ; these globular, thin and reticu- 

 lated, large, opening by a longitudinal cleft into two valves, and bearing 

 near the apex a small patch of thickened oblong cells, the rudiment of a trans- 

 verse ring. Fronds tall and upright, growing in large crowns from thickened 

 rootstocks, once or twice pinnate ; veins forking and free. Spores green. 

 (Osmunder, a Saxon name of the Celtic divinity, Thor.) 



* Sterile fronds truly bipinnate. 



1. 0. regalis L. (FLOWERING FERN.) Very smooth, paie green (0.3-1.6 m. 

 high) ; sterile pinnules 13-25, varying from oblong-oval to lance-oblong, finely 

 serrulate, especially toward the apex, otherwise entire, or crenately lobed 

 toward the rounded, oblique and truncate, or even cordate and semi-auriculate 

 base, sessile or short-stalked (2-5 cm. long) ; the fertile racemose-panicled at 

 the summit of the frond. (O. spectabilis Willd.) Swamps and wet woods, 

 common. The cordate pinnules sometimes found here are commoner in Europe. 

 May, June. (Eu.) Forma ORBICULATA Clute has narrow fronds and few 

 (3-7) roundish crowded pinnules on each pinna. Hartland, Vt. (Buggies). 



* * Sterile fronds once pinnate ; pinnae deeply pinnatifid ; the lobes entire. 



2. 0. Claytoniana L. Clothed with loose wool when young, soon smooth ; 

 fertile fronds taller than the sterile (6-12 dm. high) ; pinnae oblong-lanceolate, 

 with oblong obtuse divisions ; some (2-5 pairs) of the middle pinnae fertile, these 

 entirely pinnate ; sporangia greenish, turning brown. Low grounds, common. 

 May. Fruiting as it unfolds. (Himalayas.) Var. DtuiA Grout is a peculiar 



