CLXIV. FILICES. 627 



small, creeping, moss-like species, in wet, rocky shades, U. S., not common. 

 Stem a few inches long, filiform. Leaves less than a line in length. Spikes 

 leafy, scarcely distinguishable from the branches. July, Aug. 

 * * * Spikes indistinguishable from the branches. 



12. L. LUCIDULUM. Michx. Shining Club Moss. 



St. ascending, dichotomously divided ; Ivs. in 8 rows, linear-lanceolate, den- 

 ticulate, shining, spreading, or a little reflexed ; theca in the axils of leaves not 

 changed nor crowded into a spike. In wet woods, U. S. and Can. The foliage 

 of this species is dark green and shining, more ample than is common to the 

 genus. Stems 8 16' long, nearly erect. Leaves 3 5" long, distinctly 

 serrate. Thecae hemispherical or reniform, in the axils of the leaves near the 

 top of the stem. Jl. 



13. L. SELAGO. (L. recurvurn. Willd.} Fir Club Moss. 



St. erect, dichotomously and fastigiately branched ; Ivs. scattered, imbri- 

 cate, lance-linear, entire, rigfd and pungent, "but awnless. A smaller species 

 than the last, found on the summits of the White Mts. 1 Stems 4 8' high, 

 densely clothed with stiff, shining, spreading leaves arranged somewhat in 8 

 rows and 2 3" in length. Thecae axillary. Aug. 



ISOETES. 

 Gr. iaos, equal, ero? , the year ; from its being evergreen. 



Thecae membranaceous, oblong, cordate, 1 -celled, immersed in the 

 dilated base of the frond; spores subglobose, slightly angular, 

 attached to numerous filiform receptacles. 



I. LACUSTRIS? (I. riparia. Engelman.} Quill-wort. 



Leaves caespitose, subulate, semiterete, dilated and imbricated at base. A 

 curious aquatic, in water at or near the margin of ponds and rivers, N. Eng ! 

 and Mid. States, often wholly submersed ! Leaves or ironds numerous, tufted and 

 simple, 2 10' long, somewhat spreading, containing numerous cells divided both 

 by longitudinal and transverse partitions. Thecae whitish, imbedded in cor- 

 responding cavities in the bases of the fronds, traversed within by many threads 

 to which the numerous, small, white, granular spores are attached. Aug. Our 

 plant differs slightly from the European (with which I have compared it), but 1 

 think not specifically. 



ORDER CLXIV. FILICES. FERNS. 



Stem a perennial, creeping, horizontal rhizoma, or sometimes^ erect and arborescent. [nation. 



Fronds (fruit-bearing leaves) variously divided, rarely entire, with forked veins, mostly circinate in ver- 

 Inflorescence occupying the back or margin of the fronds (leaves) arising from the veins. 

 TheccB or sporangia ofone kind only in the same plant, 1-cellecl, dehiscing irregularly. 

 Sori, somewhat regular collections of thecae ; or the thec<e are isolated and scattered. 

 JndMsium, a scale investing each sorus ; or the sori are covered with the revolute margin of the frond, 

 or they are naked. 



Genera 192, species 2040. A large and interesting order of flowerless plants, distinguished for their ele- 

 gant, plume-like foliage. They are usually a few inches to a few feet high, but some of the tropical spe- 

 cies, as the Cyatheae of both Indies, are 1525 feet high, vicing with the palms in size and beauty. 



Properties. -Generally mucilaginous and mildly astringent, hence considered pectoral. Aspidiumand 

 Pteris are anthelmintic. Osmunda regalis has been successfully administered for the rickets. 



Observation. The fructification of the ferns, with its various appendages, is too minute to be well 

 observed by the naked eye ; but an examination of it with thu aid of a good lens, cannot fail to be inter- 

 esting and satisfactory. In regard to the localities of the terns, it should here be remarked, that the spe- 

 cies respectively are more generally disseminated throughout, the States represented by this flora, and 

 also British America, than are the species of the Phaenogamia. They are, however, far more common 

 in the hard, mountainous or rocky soils of the East than in the fertile regions of the West. It seems, 

 therefore, unnecessary to make particular mention of the geographical range of the more common species. 



Conspectus of the Genera. 

 * Fertile leaflets or fronds contracted into the form of a panicle or spike. 



(Stipes $ angular Onoclea. 11 



4 the fert. fronds < smoothish, < deeply grooved within. Struthiopteris. 12 



< distinct. . . (Stipes clothed with reddish wool. . Osmunda. 13 



(Fronds ma- 5 divided, (each one partly fertile Osmunda. 13 



! ny, radical, { entire and narrowly linear. Schizcea 15 



Fern ] (entire. Scape spicate Ophiosrlosswm. 16 



erect. I Frond solitary on a scape, ^divided. Scape paniculate Botrychiivm. 17 



Fern climbing, stem long and slender Lygodium. 14 



53 



