OsTRICH FERN. 
Plants 6 dm. or higher; sterile leaves broadly lanceo- 
late, narrowed towards the base; pinnae linear, acumin- 
ate, 12cm. more or lessin length, 1.5 cm. or less wide, 
deeply pinnatifid, lobes oblong, rounded; fertile leaves 
much shorter, pinnate. ; 
Along riverbanks. Summer. 
Gunpowder River, Md., Waters; Plummer’s Island, 
Steele; Fairfax Co., Va., Maxon. 
23. ONOCLEA L. 1753. 
Robust plants with creeping rootstocks. Leaves scat- 
tered. Fertile leaves 2-pinnate, the contracted pod-like 
divisions enclosing the sporangia. 
1. O. sensibilis L. 
Filix Osmunda facte Mariana ... Pluh. 1700, 
Mant. So. t. 404. f. 2. 
Osmunda frondtbus pinnatis : folits superioribus 
bast connatis . . Gron. 1743. Fl. 2: 196. 
Onoclea senstbilis L. Sp. Pl. 1062. Laton, Ferns 
-2:195.t. 72; in Gray, Man. 690. Underw. in Ill. 
Fl. 1:9. Nat.Ferns 120; in Britt. Man. rg. Clute, 
Ferns 253. Waters, Ferns 265. 
SENSITIVE FERN. 
Plants 3-6 dm. high; sterile leaves long-stalked tri- 
angular-ovate, 2-pinnatifid below; pinnae 15 cm. or less 
in length, 4 cm. or less wide, pinnatifid or sinuately 
lobed ; fertile leaves much reduced, 4 cm. or less high. 
Frequent in moist places, Summer, 
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