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 launches. 



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. recurvum. Willd.) Fir Club Moss. 



St. erect, dichotomously and fastigialely 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 stiff, shining, spreading leaves arranged somewhat in 8 

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



ISOETES. 



Gr. taos, equal, eroi, 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. 



L LACusTRis'? (I. riparia. Engebnan.) 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 fronds 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 (M^ith which I have compared it), but I 

 think not specifically. 



Order CLXIV. FILICES.— Ferns. 



Ste/m a perennial, creeping, horizontal rhi/oma, or sometimes erect and arborescent. [nation. 



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

 Injlorescence occupying the back or martrin of the fronds (leaves) arising from the veins. 

 Thecce or ^poranL'ia olone kind only in the same plant, 1-celled, dehiscinff irregularly. 

 Sori, somewhat re:,'ular collei'iions of thecal; ; or the Iheca; are isolated unJ scattered. 

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

 or they are naked. 



Genera 192. species 20to. A large and interesting order of flowcrless plants, distinguished for their ele- 

 gant, plumelike folintre. They are usually a few inches to a lew feet high, iiut some of the tropical spe- 

 cies, as the Cyathea; of Ixjth Indies, are 1.5—25 feet high, vieiiig with the palms in size and beauty. 



ProperticJi.—CivniinWy mucilaginous and mildly astringent, hence considered pectoral. Aspidiumand 

 Pteris are anthelmintic. Osmunda regalis him been successfully administered for the ricketa. 



Obserraiinn.—Tha fructification of the ferns, with itj* various appendages, is too minute to be well 

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

 esting and satisfactory. In regard to the loralitit-s of the fenis, it should here be remarked, that the spe- 

 cies respectively arc more jfeiurally disseminated throughout the .States represented i>y this Horn, and 

 also Bntish Amerira. than are the spe<ies nf the I'hit no^Mimia. They are, howcxtr, far more common 

 in the hard, mountainous or rocky soils of tlic Kast tlmn in the fertile rejfioiis of the West. It scenu. 

 therefore, unneco.ssary to make particular mention of the geographical ranjie oft he more common species. 

 Caiispcctm of (hr Gmrra. 

 ♦ Fertile leaflct.s or fronds contracted into the form of a panicle or .spike. 



(Sliprw Ungular Onoclra. II 



( the C>rt. fmndj ' smoothiiih, { deeply grooved within. Strut/tiopterit, 18 



^ distinct. . . f .siii»e« clo(hc<l with reddish wool. . IktmumUi. |3 



{Fronds ma- ^ divided, ( each «»M! partly fertile Ornninda. 13 



ny, radical, ^ entire and narrowly linear Schizirn. 15 



(entire Hcupc spiratc Ophioirloasutn. \6 



Frond solitJiry, on a .sr^pe, ) divided. fjcaj>e paniculate. . Eotnjchium. 17 



Fern climbing, stem long luid slender. Lygodiuut. m 



53* 



