Oedeb 160.— FILICBS. 817 



the ultimate segments being deourrent and more or less confluent at base, with 

 3 — 5 out serratures. Panicle terminal, 3 — 6' long, reddish-tawny. June, July. 



3. LYGO'DIUM Swartz. Climbing Fern. (Gr. AvyoJeST/c, flexible, 

 slender ; from the habit.) Sporangia sessile, aiTanged in 2-ranked 

 spikelets issuing from the margin of the contracted frond, opening on 

 the inner side from the base to the summit; indusium a scale-like veil 

 covering each sporangc. (Fig. 109.) 



Ii. paliu^tum Sw. Stem flexuoua, climbing; fronds conjugate, palmate, 5-lobed, 

 lobes entire, obtuse; spikelets oblong-linear, from the upper fronds, which are 

 divided and contracted into a compound spike. — This is one of the few ferns with 

 climbing stems, and the only one iband in the U. S., Mass. to Ky. and S. States, 

 rare. Plant of a slender and delicate structure, smooth. Stem 3 — if long. Stipes 

 alternate on the stem, forked, supporting a pair of fronds which are palmately 

 divided into 5 — 9 segments. Fertile fronds terminal, numerously subdivided into 

 linear-oblong segments or spikelets, with the fruit in 2 rows on the back. July. 



4. SCEflZ^^A Smith. (Gr. <jxi-^(^, to cut, cleave ; alluding to the 

 many-cleft spikes.) Sporangia oval, radiate at top, sessile, bursting later- 

 ally ; indusium continuous, formed of the inficxed margins of the leaf- 

 lets which are contracted, spike-like, crowded at the summit of the fertile 

 frond. 



S. pusilla Pursh. Frond simple, linear, tortuous; spikes few, crowded at the 

 top of a long, slender stipe or scape. — A very delicate fern, found in the pino 

 barrens, Quaker Bridge, N. J., also in Western N. T. (by Mr. Timothy 'Westmore). 

 Fronds numerous, coespitous, 2 — 3' long, \ — 1" wide. Fertile stipes several, 3 — 6' 

 high, filiform, with a few short, unilateral spikelets at top arranged in 2 rows. 

 Capsules somewhat turbinate, in 2 rows on the inner side of each spikelet. Aug. 



5. OSMUN'DA, L. Flowering Fern. Sporangia globular, half 2- 

 valved, roughened on the surface somewhat in lines, pedicellate and 

 clustered on the lower surface of the frond or a portion' of it, which is 

 more or less contracted into the form of a panicle ; spores green. — ^Tall, 

 handsome Ferns. Veins forked, straight. 



I Frond bipinnato T\-ith distinct pinnse; tlio upper part contracted and fertile Wo. 1 



§ Frond i)innate with pinnatifld pinnai, x>a''tially or separately fertile Nos. 2, 3 



1 O. regalis Mx. Fronds bipinnate, fructiferous at the summit ; segments of tho 

 leaflets lance-oblong, distinct, serrulate, subsessile ; raceme large, terminal, decom- 

 pound. — A large and beautiful fern, in swamps and meadows. The fl-onds are 

 3 — 4f high, smooth in all their parts. Leaflets or pinnas opposite, remote, each 

 with 6 — 9 pairs of leaves with an odd one. These are an incli or more long, \ as 

 wide, obtuse, the petioles — J-" long. Above, the frond is crowned with an ample 

 bipinnate panicle of a deep fulvous hue, with innumerable, small, globular, 2- 

 vived spore-oases covering the segments. Jn. (0. spectabilis Willd.) 



2 O. oiunamomea L. Cinnamon Feen. Sterile frond pinnate, leaflets elongated, 

 pinnatifld, segments ovate-oblong, obtuse, very entire; fertile frond iipinnaie, 

 leaflets ail contracted, paniculate, subopposite, kmuginotts as well as the stipe. — This 

 is among the largest of our ferns, growing in swamps and low grounds. Fronds 

 numerous, growing in clumps, 3 — 5f high, most of them barren, the stipe and 

 racliia invested with a loose, cinnamon-colored wool. The fertile fronds resemble 

 spikes, 1 — 2f long, an inch wide. Leaflets all fertile, erect, with the segments 

 covered with fruit in the form of small, roundish capsules, appearing, under a 

 microscope, half-2-cleft. June. 



3 O. Claytoniana L. Intekeupted FLOWEEnre Fern. Frond smooth through- 

 out, pinnate with lance-linear pinnatifld Ifts. ; lobes obtuse, entire, the veinlets all 

 once forked, some (2 to '7) of the intermediate leaflets fertile. — Common in low 

 grounds. Fronds ample, 2 to 3f high, light green, interrupted near the middle 

 by 2 to 4 pairs of fertile leaflets, which are so much metamorphosed as to resemble 

 dense, compound* racemes, densely covered with small reddish-brown sporangia. 



62 



