$16 Obdbb 160.— FILICES. 



g Fruit-dots dorsal, oblong or linear, parallel with the midvein Woodwardia. 13 



g Fruit-dots dorsal, oblong or linear, transverse to the midvein. (k) 



k Indusia single, regularly arranged in 2 rows Asplenium. 14 



k Indusia single, scattered irregularly, placed angularly Antigramma. 15 



k Indusia double, regularly arranged. Frond simple Scolopendrium. 14 



g Fruit-dots dorsal, orbicular, (o) 



O Indusium cup-shaped, fixed beneath all around the sorus "Woodsia. IT 



O Indusium hood-shaped, fixed at the base and 2 sides Cistottaris. 18 



O Indusium peltate or renifm, — all involved in the berry like segm.ONocu'.A. 19 

 — all superficial on the fiat segm, Aspidivm. 24 



1. OPHIOGIOS'SUM, L. Adder's Tongue. (Gr. %?, a serpent, 



yXcJaaa, tongue.) Sporangia roundish, depressed, opening transversely, 

 arranged in two rows along the margins of the fertile frond which h 

 contracted into a linear spike ; indusium none, veins reticulated. 



1 O. vulgatum L. Frond simple, oblong-ovate, obtuse, reticulations elongated; 

 spike cauline, root of thick spreading fibres. — A curious little plant in low grounds. 

 Fronds solitary, 2 — 3' long, §- as wide, amplexicaul, entire, smooth, •without & 

 midvein, situated upon the stem or stipe a little below the middle. Stipe G — 10' 

 high, terminating in a lance-linear, compressed spike, 1 — 2' long, with the fruit 

 arranged in 2, close, marginal ranks. Sporangia opening outwards end horizontally, 

 becoming lunate, distinct, straw-colored. Vernation straight, not circulate. June. 



2 O. bulbdsum L. Frond simple, ovate or orliculate, or reniform, sutcordate, 

 nearly or quite radical, obtuse ; reticulations short, spike cauline ; root a subgloloiut 

 bulb. — Wet pine barrens, N. J. (Pursh) to Ga. and La. Sts. about 3' high', often 

 2 from the same bulb, spike short, oblong (4 to 8"). Lvs. 2 or 3, one of them 

 cauline. Bulbs, 3 to G" diani. 



2. BOTRYCHIUM, Swartz. Moonwort, Grape Fern. (Gr. porpi •?, a 

 cluster of grapes ; from the resemblance of the fructification.) Sporangia 

 Kubglobous, 1-cellcd, 2-valvcd, distinct, coriaceous, smooth, sdnate t« 

 the compound rachis of a racemous panicle ; valves opening transversely. 



§ Frond ternately divided, situated near the base of the stipe or stem Nos. 1, t 



§ Frond pinnately divided, situated at or above the middle of the stem Nos. 3, 4 



1 B. lunarioides Swartz. Scape bearing the frond near the base; frond in 'A 

 bipinnaiifid divisions ; segments obliquely lanceolate, crenulate ; spikes bijinnate. 

 — Native of shady woods and pastures. Frond almost radical, of a triangular 

 outline, 3 — 5' long and wide, of a stouter texture than No. 4, distinctly pt tiolate. 

 Scape thick, 8 — 12' high, bearing a tawny, compound panicle 2 — 4' in lergth, 

 composed of numerous littlo 2-ranked spikes. Aug. (B. obliquuni Muhl. B. 

 fumarioides Willd.) 



/3. dissectum. Frond near the base of the scape, more numerously dissected, 

 almost tripinnatilid. (B. dissectum "Willd.) 



2 B. simplex Hitchcock. Frond female, borne near half way up the stalk; Ifts. 

 cuneate-obovate, subeniire or incised, unequal ; spike compound, interrupted, uni- 

 lateral; capsules sessile, yellow. — Dry hilly pastures, Vt. and Mass. Stipe or 

 pcape 3 to G' high. Closely resembles 11. lunaria of Eur. Frond varies* from 

 simply ternato to ternate-pinuatifid. Jn. 



3 B. neglectum. Meriden Moonavort. Frond simply pinnate, with oblong- 

 ovate or oval, incised leaflets, and borne near the summit of the scape ; capsules 

 pedicellate, subsolitary, in an oblong panicle. — Rocky woods, N. It. (Mcridcn !) 

 Allied rather to the next than to No. 1. St. 5 to 8' high. Frond 9 to 20" long, 

 half as wide. Lfts. 3 or 4 pairs. Pan. often larger than the fronds. Caps, brown- 

 ish, on very short, thick stipes. July. 



4 B. Virginicum L. Rattlesnake Fern. Stipe with a single frond in the mid- 

 dle; frond twice and thrice pinnate, the lowest pair of pinnse springing from the 

 base; ultimate segments obtuse, somewhat 3-toothed ; spikes decompound ; plant 

 subpilous. — A beautiful fern, the largest of its genus, in low woods. Stipe or 

 scape 1 — 2f high, bearing the frond about half-way up. This is apparently ter- 

 nate, the lower pair of divisions arising from the base. It is almost tripinnate, 



