28 NORTH AMERICAN FLORA [VorumME 16 
2. Osmunda regalis I. Sp. Pl. 1065. 1753. 
Osmunda spectabilis Willd. Sp. P1.5: 98. 1810. 
Osmunda glaucescens Link, Fil. Sp. 20. 1841. 
Osmunda mexicana Fée, Mém. Foug. 9: 43 (34). 1857. 
Rhizomes and root-masses subterranean or partly aérial, forming tussocks, the roots 
black ; leaves 35-180 cm. long, partly dimorphic, the stipes 15-60 cm. long, the sheathing 
bases abruptly narrowed above but not lobed, the stipe and rachis smooth, brown or dark- 
stramineous, polished, glabrous when mature; sterile lamina broadly oblong, 25-120 cm. 
long, 20-30 cm. broad, obtuse or broadly acute, bipinnate, the pinnae conformably divided, 
distant, strictly paired and nearly opposite, oblong to ovate-lanceolate or deltoid-ovate, 11- 
40 cm. long, 6-13 cm. broad, broadly acute, oblique, straight, glabrous, dull-green, the 
pinnules rather distant, very short-stalked, straight, the lateral pinnules oblong, 2-7.5 cm. 
long, 0.5-2 cm. broad, acute, with unequally truncate to rounded bases, the terminal seg- 
ment lanceolate, broader, with a cuneate base; veinlets mostly 2-forked; fertile lamina in 
general like the sterile one but usually narrower, owing to the very oblique habit of the 
pinnae, and with the pinnae in the upper third of the lamina much reduced and contracted, 
the fertile pinnules mostly erect, consisting of a narrowly winged midvein, and the thick- 
ened shortened often forked veinlets densely covered with the cinnamon-brown sporangia. 
TYPE LOCALITY: Europe. 
DISTRIBUTION: Eastern North America, Mexico, and the West Indies; also in South America, 
Europe, Asia, and South Africa. 
ILLUSTRATIONS: D. C. Eaton, Ferns N. Am. f/. 28 ; Lowe, Ferns Brit. & Exot. 8: fi. 1; Britt. 
& Brown, Ill. Fl. # 8. 
3. Osmunda Claytoniana L. Sp. Pl. 1066. 1753. 
Osmunda interrupia Michx. Fl. Bor. Am. 2: 273. 1803. 
Osmunda basilaris Spreng. Anleit. 3: 160. 1804. 
Plenasium Claytoniana Presl, Abh. BOhm. Ges. Wiss. V.5: 325. 1847. 
Plenasium interruptum Presi, Abh. BGhm. Ges. Wiss. V.5: 325. 1847. 
Rhizomes and root-masses subterranean, the roots dark-brown; leaves 30-150 cm. 
long, partly dimorphic, the stipes 9-65 cm. long, the sheathing base narrowing at an acute 
angle into the upper part, the stipe and rachis glabrous when mature; sterile lamina nar- 
rowly oblong or lanceolate, 19-85 cm. long, 7-30 cm. broad, abruptly short-acuminate, pin- 
nate, the pinnae deeply pinnatifid, mostly in pairs, at least below, but not exactly opposite, 
oblong or somewhat lanceolate, 5-15 cm. long, 1.5-3.5 cm. broad, straight or slightly 
recurved, rather short-acute, often bluntish, nearly glabrous but with scattered brown 
hairs along the veinlets below, dull-green, the segments close, mostly straight, with the 
anterior margin usually straight, oblong, mostly blunt or rounded ; veinlets once-forked ; 
fertile lamina in general like the sterile but with 1-4 pairs of fertile pinnae near (usually 
just below) the middle of the lamina, the fertile pinnae pinnate, deltoid, strongly falcate, 
about half as long as the sterile pinnae, the segments crowded, either consisting only of 
the midveins and the thickened shortened veiulets on which the dark-brown sporangia are 
thickly borne, or sometimes narrowly winged. 
TYPE LOCALITY: Virginia. 
DISTRIBUTION: Newfoundland to Minnesota, southward to North Carolina and Missouri ; also 
in India and China. 
ILLUSTRATIONS: D. C. Eaton, Ferns N. Am. #1. 29, f. 1, 2; Lowe, Ferns Brit. & Exot. 8: pl. 3; 
Meehan’s Mo. 4: p/. 10; Britt. & Brown, Hl. Fl. f 10. 
