CLXIV. FILICES. 1327 



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 indislinuui^fiablc from the braiicfics. 



12. L. LUciDULUM. Michx. Shining Club M>ss. 



SI. ascending, dicholomouslv divided ; lis. in 8 rows, linear-lanceolate, den- 

 ticulate, .shining, spreading, or a'litlle rellcxed; f/uac 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— IG' long, nearly erect. Leaves 3—5" long, di.stinctly 

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

 top of the stem. Jl. 



13. L. sELAGo. (L. rccurvum. W'dld.) Fir CliU) Moss. 



St. erect, dichotoniously and lastigiaicly branched ; Ivs. scattered, imbri- 

 cate, lance-linear, entire, rigid and pungent, but awnless.— A smaller species 

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

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

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



ISOETES. 



Gr. laos, equal, CToi, the year ; from its being eversrccn. 



Thecce 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. Engdmaii.') Quill-wort. 



Leaves csespitose, subulate, seraiterete, dilated and imbricated at base. — A 

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

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

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

 by longitudinal and transverse partitions. Theca? whitish, imljcdded 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.— Fer^s. 



Stem a perennial, creeping, horizontal rlii-roma, or sometimes erect and arborescent. [nation. 



Fronds (fruit-bearing leaves) variously divided, rarely entire, witli forked vein.s, mostly circinate in ver- 

 InjUrrescence. occupyinK the back or margin of the fronds (leaves) arising from the veins. 

 Thec<R or sporangia of one kind only in the same plant, l -celled, dehiscing irregularly. 

 Sori, somewhat regular collections of iheca; ; or the thecao are isolated and scattered. 

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

 or they are naked. 



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

 gant, plume-like foliiige. They are usually a few niches to a tew fuet high, but some of the tropical spe- 

 cies, as the Cyatheai of both Indies, are 15—25 feet high, vieing with the palms in size and beauty. 



Properties.— GcnexM^- mucilaginous and mildly astringent, hence considered i)ectoral. Aspidiiunand 

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



Obserration.— 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 the aid of a good lens, cannot fail to be inter- 

 esting and satisfactorj-. In regard to the localities of the ferns, it should hcie be remarked, that the spe- 

 cies respectively are more generally disseminated throughout the .States reiiresentcd by this floni. and 

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

 in the hard, mountainous or rocky soils of the East th;ui 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 Gcji^ra. 

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



(Stipes Umguiar Onoclea. 11 



( the fert. fronds-' smoothish, I deeply grooved within, Strut/iiopteris. 12 



< distinct, . . ( Stipes clothed with reddish wool. . Own/;?<to. 13 



f Fronds ma- divided, ( eacli one partly fertile Ouninda. 13 



I ny, radical, ( entire and narrowly linear Sch/zara. 15 



Fern | t entire. ScApe spicate Ophios'/ossvm. \S 



erect. I Frond solitary, on a scape, {divided. Scape paniculate Botrychium. 17 



Fern climbing, stem long and slender Lygodium. 11 



53* 



