600 FILTCES. (FERNS.) 



SUBORDER II. OSMUNDl'lVEJE. FLOWERING-FERN FAMILY. 



16. SCHIZJEA, Smith. SCHIZ^A. (Tab. 13.) 



Fertile fronds of several contracted linear pinnae, which are approximated in 

 pairs at the apex of a slender stalk; the under (inner) side covered with the 

 fructification, consisting of two rows of sessile naked sporangia, which are oval, 

 vertical, furnished with a striate-raycd crest at the apex, and opening by a lon- 

 gitudinal cleft down the outer side. Sterile fronds linear or thread-like, some- 

 times forked and cleft (whence the name, from oxtfco, to slit). 



1. S. pusilla, Pursh. Sterile fronds linear-thread-form, simple, tortuous, 

 much shorter than tho, fertile, which bears about 5 pairs of short crowded pinnae 

 at the apex of a slender stalk (3' -4' high). Low grounds, pine barrens of New 

 Jersey; rare. 



17. L,YGODIUITI, Swartz. CLIMBING FERN. (Tab. 13.) 



Fronds twining or climbing, bearing stalked and variously lobed divisions in 

 pairs, with free veins ; the fructification on separate contracted divisions or spike- 

 like lobes, one side of which is covered with hooded scales for indusia, imbri- 

 cated in two ranks, fixed by a broad base, each enclosing a single sporangium, or 

 rarely a pair. Sporangia much as in Schizsea, but oblique, fixed to the vein by 

 the inner side next the base. (Name from \vyd>8ijs, flexile.) 



1. L. imlilifttlBin, Swartz. Very smooth; stalks slender, flexile and 

 twining (l-3long), from slender running rootstocks ; the short alternate 

 branches or petioles deeply 2-forked, each fork bearing a rounded heart-shaped 

 palmately 4-7-lobcd sterile frondlet; fertile frondlets above, contracted and 

 several times forked, forming a terminal panicle. (Hydroglossum, Willd.) 

 Shaded or moist grassy places, Massachusetts to Virginia, Kentucky, and spar- 

 ingly southward ; rare. July. 



18. OSUIUNDA, L. FLOWERING FERN. (Tab. 13.) 



Sporangia globular, short-pedicelled, naked, entirely covering the fertile fronds 

 or certain pinnae (which arc contracted to the mere rhachis), thin and reticulated, 

 not striate-rayed at the apex, opening opposite the pedicel into two valves. 

 Spores green. Fronds tall and upright, from thickened rootstocks, 1 -2-pinnate : 

 veins forking and free. (Osmunder, a Saxon name of the Celtic divinity Thor.) 

 # Fronds twice pinnate, fertile at the top. 



1. O. regftlis, L. (FLOWERING FERN.) Very smooth, pale green 

 (2 -5 high); sterile pinnules 13-25, lance-oblong, more or less serrulate, 

 otherwise mostly entire, oblique (or often auricled on the lower side) at the 

 nearly sessile base (1 -2 long); the fertile racemose-panieled at the summit of 

 the frond. (Ku.) 



Var. SpectiibiliS. Pinnules ordinarily narrower and less auricled, or ob- 

 liquely truncate at the *//>//<//*/ Ktdlknl base. (O. speetalulis, Willd.) Swamps 

 and wet woods ; common. June, July. 



