BOTRYCHIUM. CLXIV. FILICES. ti35 



long, rather acute, entire ; some of the intermediate leaflets fertile. A large 

 fern in low grounds. Fronds 2 3f high, light green, interrupted near the mid- 

 dle by 2 4 pairs of fertile leaflets, which are so much contracted in size as to 

 resemble dense, compound racemes, and densely covered with small reddish- 

 brown thecae. Stipe channeled, smooth above, chaffy at base. June. 



14. LYGODIUM. Swartz. 



Gr. Xvybxfe;, flexible, slender; from the slender, climbing habit. 



Thecse sessile, arranged in 2-ranked spikelets issuing from the 

 margin of the frond, opening on the inner side from the base to the 

 summit ; indusium a scale-like veil covering each theca. 



L. PALMATUM. Sw. Climbing Fern. 



Stem flexuous, 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 found in the U. S. Plant of a slender and delicate 

 structure, smooth. Stem 3 4f long. Stipes alternate on the stem, forked, 

 supporting a pair of fronds which are palmately divided into 5 9 segments. 

 Fertile fronds termins.1, numerously subdivided into linear-oblong segments or 

 spikelets, with the fruit in 2 rows on the back. Mass. ! to Penn., &c. July. 



15. SCHIZ^EA. Smith. 



Gr. <TXIO), to cut, cleave ; alluding to the many-cleft spikes. 



Spikes unilateral, flabelliform, aggregate ; thecce roundish, radiate 

 at top, sessile, bursting laterally ; indusium continuous, formed of the 

 inflexed margins of the spikes. 



S. PCSILLA. Pursh. (S. tortuosa. MvM.~\ 



Frond simple, linear, tortuous; spikes few, crowded at the top of a long, 

 slender stipe or scape. A very delicate fern, found in the pine barrens, Quaker 

 Bridge, N. J., also in Western N. Y. by Mr. Timothy Westmore! Frorids nu- 

 merous, caespitose, 23' long, * I" wide. Fertile stipes several, 3 6' high, 

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

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



TRIBE 3. OPHIOGL.OSSEJE. Thecae 1-celled, adnate at base, subglobose, 



coriaceous, opaque, half-2-valved, not cellular, and destitute of a ring. 



16. OPHIOGLOSSUM. 



Gr. o^i j, a serpent, yAotnra, tongue; from the resemblance. 



Thecae roundish, opening transversely, connate, arranged in a 

 2-ranked, articulated spike. 



0. VULGATUM. Adder's Tongue. 



Frond simple, oblong-ovate, obtuse, closely reticulated; spike cauline. -A 

 curious little plant in low grounds. Fronds solitary, 2 3' long, | as wide, 

 amplexicaul, entire, smooth, without a mid vein, situated upon the stem or stipe 

 a little below the middle. Stipe 610' high, terminating in a lance-linear, 

 compressed spike, 1 2' long, with the thecoe arranged in 2, close, marginal 

 ranks. Thecse opening outwards and horizontally, becoming lunate, distinct, 

 straw-colored. Vernation straight, not circinate. June. 



17. BOTRYCHIUM. Swartz. 



Gr. /?orpvj, a cluster of grapes ; from the resemblance of the fructification. 



Thecoe subglobose, 1-celled, 2-valved, distinct, coriaceous, smooth, 

 adnate to the compound rachis of a racemose panicle ; valves open- 

 ing transversely. 



1. B. NEGLECTUM. Wood. Meriden Botrychium. 



Stipe bearing the frond near the top ; frond simply pinnate, very short, 

 with subentire or subpinnatifid segments,; spikes paniculate. A singular species, 

 54 



