FILICES. 4.65 



15. DICKSONIA. VHerit.—Dicksoma.. 

 (In honor oi James Dickson, an English botanist.) 



Sori small, roundish or dot-like, distinct, marginal. Indu- 

 sium coriaceous or membranaceous, formed in part of the lobule 

 of the frond and of the proper indusium- more or less united, 

 2-valved or entire, sometimes cup-shaped. 



D. pilosiuscula WiUd.: frond bipinnate ; pinnae lanceolate, sessUe; pin- 

 nules decurrent, ovate-oblong, pinnatifid; segments incised-toothed ; son 

 solitary, minute ; indusium cup-shaped. D. punctiloha Hook. NepJirodium 

 punctilobum Mich. Aspidium punctilobum Willd. 



Moist shady places. Can. to Virg. ; common July. '^■-^'•1''^^^-'^^^^^^^^ 

 hi-h lance-oblong, somewhat hairy, pale yellowisb-green and rather delicate. 

 k^e and rac;.i. fomewhat hairy, pale green. Son ^oht^^y^^^}^''£l£^^^^ 

 divisions of the segments. ^^'"^ Vicksoma. 



II. OsMUNDEiB. Capsules destitute of a ring, reticulated, striated 

 with rays at the apex, opening lengthwise and usually externally. 



16. OSMUNDA. Z^WMi.— Flowering Fern. 



(Etymology uncertain.) 

 Spore-cases subglobose, pedicellate, radiate-striate or wrin- 

 kled, half 2-valved, in terminal paniculate racemes, or clustered 

 on the contracted frond. Indusium none. ^ 



1 O Claytoniana Linn.: frond pinnate; pinna pinnatifid; segments 

 oblong, entire; some of the intermediate pinna fertile. O. interrupta 



2 O spectabUisLinn.: frond bipinnate, fruit bearing at th5 summit; 

 pinnules lance-oblong, nearly equal at the base, subpetiolate, serrulate; 

 raceme large, decompound, smooth. O. regalis Mich o . ^ , i,- i 



Moist meadows and thickets. Can.toFlor. July. ^.-Fem 3-^ feet high, 

 «mootf Ta^sTgreen, with numerous spreading branches Eacme termina , 

 4-8 incheXng Smaller and of a more rigid texture than the foreign O reg-aZ^, 

 L\£fdSg fromit in having the pinnules distinct and -^^f^^^^J^-^^ 

 on the lower side. 



3 O cinnamomeaLinn.: sterile frond pinnate; pinnae elongated, pin- 

 natifid; segments ovate-oblong, entire; fertile frond bipinnate ; pinnae con- 

 tracted, and with the stipe woolly. 



var frondosa Torr.: frond leafy below, fruit-beanng at the summi ; 

 stipe less woolly. O. .Claytoniana Conrad not of Linn, (according to 

 Torr.) 



