Opkiog-lossum, Boirychimn. 99 



clothed when young with ferruginous tomentum ; sterile fronds 

 smooth when mature, the pinnse lanceolate, cut into broadly ob- 

 long, obtuse, divisions ; fertile fronds contracted, bipinnate, with 

 cinnamon-colored sporangia. In var.frondosa, Gray, some of the 

 fronds are sterile below and sparsely fertile at the summit. N. E. 

 and Wis. to Fla. III. 



XXX. OPHIOGLOSSUM, L. Adder-tongue. 

 Sporangia large, coriaceous, connate, coherent in two ranks on 



the edges of a simple spike. Veins anastomosing. Spores co- 

 pious, sulphur-j'ellow. 



I I. EUOPHIOGLOSSUM. Fertile spike single arising of 

 the base of the sterile segment. 



* Sterile portion near the middle of the stalk. 



1. O. vulgatuiii, L. Rhizoma short, oblique; stalk 6' — 12' 

 high, the sterile segment ovate or elliptical-oblong i>^' — 4' long, 

 somewhat fleshy, somewhat narrowed at the base, sessile ; fertile 

 spike 1' or more long. Me. to Ky., Tenn., Tex. and Ariz. III. 



** Sterile portion near the base of the stalks. 



2. O. crbtalophoroides, Walt. Rhizoma tuberous, 3"— 5" thick; 

 stalk 3' — 6' high, the sterile segment yi' — \' long, ovate, slightly 

 petioled, the veins somewhat indistinct ; fertile spike short and 

 thick, 3"— 6" long. (O. bulbosum, Michx.) Fla. to La. VI. 



3. O. nudicaule, Linn, f Rhizoma slightly tuberous ; stalk 

 I'— 4' high, the sterile segment yi' — \yi' long, ovate or oblong, 

 the veins indistinct ; fertile spike linear-acuminate, 6" long, the 

 peduncle very slender. Fla., Ga. VI. 



\ 2. CHEIROGLOSSA, Presl, Fertile spikes several, arising 

 from the base of the sterile segment. 



4. O. palmatum, Plumier. Rhizoma fleshy, tuberous, covered 

 with fine wool-like chaff; plant fleshy, 6' — 2° high, the sterile seg- 

 ment cuneate at the base, 2 — 6 lobed or rarely entire, the lobes 

 elongated and tapering ; fertile spikes i — 8 or more, borne on the 

 sides of the stipe just below the sterile segment or on its margin. 

 Fla. VI. 



XXXI. BOTRYCHIUM, Swz. Grape-fern. 

 Rhizoma very short, erect, with clustered fleshy roots, the bud 



for the next year's growth usually imbedded in the base of the 

 stipe. Sterile segment of frond pinnately or ternately divided or 

 compound. Fertile segment i — 3 pinnate with double rows of 

 sessile, naked sporangia. Veins free. Spores copious, sulphur- 

 yellow. 



