600 FILICES. (FERNS.) 



SUBORDER II. OSMUNDINEJE. FLOWERING-FERN FAMILY. 



16. CIIIZ/EA, 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-rayed 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 <rxifa, to slit). 



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

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

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

 Jersey; rare. 



17. LYGODIUJH, 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 Schizaea, but oblique, fixed to the vein by 

 the inner side next the base. (Name from AvyooSqs, flexile.) 



1. li palltiaXuni, 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-lobed 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. OS M LINDA, L. FLOWERING FERN. (Tab. 13.) 



Sporangia globular, short-pedicellcd, naked, entirely covering the fertile frond* 

 or certain pinnae (which are 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. regfklis, 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 1 long) ; the fertile racemose-panicled at the summit of 

 the frond. (Eu.) 



Var. Specti1>ilis. Pinnules ordinarily narrower and less auricled, or ob- 

 liquely truncate at the slightly stalked base. (O. spectabilis, Willd.) Swamps 

 and wet woods ; common. June, Julv. 



