/■ 



596 FILICES. (ferns.) 



obtuse, crenately pinnatifid-toothed, with a single smooth fiuit-dot just below 

 the sinus between each rounded minutely -toothed lobe. (W. Perriniana, Hook. 

 Sf Grev. Aspidium obtusum, Willd.) — Rocky banks and cliffs; common, es- 

 pecially westward. July. 



§2. WOODSIA Proper. — Indusium minute or evanescent, open and flattened 

 from an early stage and concealed under the fruit-dot, except the fringe of bristly- 

 cl taffy hairs into which its margin is dissected. 



2. W. IlveilSiS, R. Brown. Frond oblong-lanceolate (2' -4' long by 1' 

 wide), smoothish and green above, thickly clothed underneath as well as the stalk 

 with rusty bristle-like chaff, pinnate ; the pinnae crowded, oblong, obtuse, sessile, 

 pinnately parted, the numerous crowded pinnules oblong, obtuse, obscurely creuate, 

 almost coriaceous, the fruit-dots near the margin, somewhat confluent when old. 

 (Nephrodium rufidulum, Michx.) — Exposed rocks, common, especially north- 

 ward, and southward in the Alleghanics. June. (Eu ) 



3. W. glntoeSBsi, R.Brown. Smooth and naked throughout ; frond linear 

 (2' -5' high), pinnate ; pinnae rather remote towards the short stalk, rhombic-ovate, 

 very obtuse (2" - 4" long), cut into 3-7 rounded or somewhat wedge-shaped lobes. — 

 Rocks, Little Falls, New York ( Vasey) ; Willoughby Mountain, Vermont ( Wood, 

 C. C. Frost) ; and high northward. 



13. CYSTOPTEBIS, Bernhardi. Bladder-Fern. (Tab. 12.) 



Fruit-dots roundish, borne on the back of a straight fork of the free veins ; 

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

 side (towards the midrib) partly under the fruit-dot, early opening free at the 

 other side, which looks toward the apex of the lobe, and is somewhat jagged, 

 soon thrown back or withering away. — Tufted Ferns with slender and deli- 

 cate 2-3-pinnate fronds; the lobes cut-toothed. (Name composed of kvo-tis, 

 a bladder, and 7rTepiV, Fern, from the inflated indusium.) 



1. C. bulMfera, Bernh. Frond lanceolate, elongated (l°-2° long), 2- 

 pinnate; the pinnae lance-oblong, pointed, horizontal (1'- 2' long); the rhachis 

 and pinna: often bearing bulbleis underneath, wingless ; pinnules crowded, oblong, 

 obtuse, toothed or pinnatifid ; indusium short, truncate on the free side. (As- 

 pidium bulbiferum, Swartz. A. atomarium, MM. !) — Shaded, moist rocks ; 

 common. July. 



2. C. fi'segilis, Bernh. Frond oblong-lanceolate (4' -8' long, besides the 

 stalk which is fully as long), 2 - 3-pinnate ; the pinna? and pinnules ovate or lan- 

 ceolate in outline, irregularly pinnatifid or cut-toothed, mostly acute, decurreni 

 on the margined or winged rhachis ; indusium tapering or acute at the free end. — 

 Var. dentata, Hook, is narrower and less divided, barely twice pinnate, with 

 ovate obtuse and bluntly-toothed pinnule* . (Aspidium tenuc, Swartz.) — Shaded 

 cliffs ; common : very variable. July. (Eu.) 



14. ASPIDIUM, Swartz. Shield-Fern. Wood-Fern. (Tab.12.) 



Fruit-dots round or roundish, borne on the back or sometimes on the ex- 

 tremity of (in our species) pinnate and free veins, scattered, or sometimes 



