Aspidium, Nephrolepis, Cystopteris. 93 



surface more or less chafTy-fibrillose ; sori in two rows on the 

 segments nearer the midvein than the edge. Cal. IV. 



Var. Californicum, D. C. Eaton. Fronds elongated, narrow, 

 tapering slightly at the base ; pinnee but slightly incised above the 

 middle, more and more deeply cleft toward the rachis, the lower 

 superior segment largest, but scarcely distijact as a pinnule, and 

 not at all auricled. [A. Californicum, D. C. E.) Cal. IV. 



Var. angulare, D. C. Eaton. Fronds oblong-lanceolate, scarcely 

 or not at all narrowed at the base, truly bipinnate ; pinnules dis- 

 tinctly short-stalked, mostly auricled and slightly incised ; the 

 basal one largest and again pinnatifid; under surface chafify-fibril- 

 lose. Cal. IV. 



Var. Braunii, Koch. Fronds oblong-lanceolate ; pinnae nu- 

 merous, oblong-lanceolate, the lower gradually reduced in size 

 and obtuse ; pinnules ovate or oblong, truncate and almost rect- 

 angular at the base, sharply toothed, beset with long soft hairs as 

 well as chaffy ones. Me. to N. Y. and northward. II. 



\ 3. CYRTOMIUM, Presl. Indusium as in | 2; fronds simply 

 pinnate with broad pinnte ; veinlets usually uniting slightly near 

 the margin. 



22. A. juglandifolium, Kunze. Stipes tufted, clothed below 

 with large scales; fronds 6' — 2° long, coriaceous; pinnae 2^12 

 pairs, short-stalked, ovate-oblong or broadly lanceolate, the ter- 

 minal one distinct, and in small fronds the largest, appressed-ser- 

 rulate, smooth on both surfaces; veins pinnated, the veinlets few, 

 free or uniting near the margin ; sori scattered in several irregular 

 rows. Western Tex. V. 



XX. NEPHROLEPIS, Schott. 



Sori round, arising from the apex of the upper branch of a 

 vein, usually near the margin. Indusium reniform or roundish. 

 Veins all free, the fronds simply pinnate, the pinnse articulated at 

 the base, and bearing white cretaceous dots on the upper surface. 



I, N. exaltata, Schott. Stipes tufted, 4' — 6' long, naked or 

 slightly scaly; fronds i°— 6° long, 3' — 6' broad; pinnae close, lan- 

 ceolate, the edge entire or slightly crenate, the upper side auricled 

 at the base, the lower rounded ; rachis nearly naked ; sori sub- 

 marginal ; indusium firm, distinctly reniform. Fla. VI. 



XXI. CYSTOPTERIS, Bernh. Bladder-fern. 

 Sori roundish, borne on the back of the veins. Indusium deli- 

 cate, hood-like, or arched, attached by a broad base on the inner 



