44 POLYPODIACEAE (FERN FAMILY') 



irregular pieces or lobes. — Small and tufted pinnately divided ferns. (Dedi- 

 cated to Joseph Woods, an English botanist.) 



* Stalks obscurehj articulated some distance from the base; fronds chaffy or 

 smooth, ni'ver glandular ; indusium divided nearly to the center into slender 

 hairs which are curled over the sporangia. 



1. W. ilvensis (L.) R. Br. Frond oblong-lanceolate (5-15 cm. long, 2-4 

 cm. wide), smoothish and green above, thickly clothed underneath as toell as the 

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

 sessile, pinnately parted, the numerous crowded segments oblong, obtuse, 

 obscurely crenate ; the fruit dots near the margin, somewhat confluent when 

 old. — Exposed rocks ; arctic Am., s. to N. E., the Great L. region, and in the 

 mts. to N. C. June. (Eurasia.) 



2. W. alpina (Bolton) S. F. Gray. Frond narrowly oblong-lanceolate (4-13 

 cm. long, 6-34 mm. wide), smooth above, sparingly paleaceous-hirsute beneath, 

 pinnate ; the pinnae triangular-ovate, obtuse, pinnately lobed, the lobes few and 

 nearly entire; fruit dots rarely confluent. (IF. hyperborea R. Br.) — N. B., 

 Que., n. Vt., n. N. Y., Out., and northw. ; rare. (Eurasia.) 



3. W. glabella R. Br. Smooth and naked throughout ; frond linear and 

 very delicate (4-16 cm. high), pinnate ; pinnae roundish-ovate, the lower ones 

 rather remote (3-9 mm. long), obtuse, crenately lobed ; fruit dots scanty ; the 

 hairs of the indusium fewer than in the last two species. — On moist mossy rocks, 

 Nfd. to n. N. E., N. Y., Minn , and northw. to Alaska and Green) (Eurasia.) 



* * Stalks not articulated; fronds never chaffy, often glandular-pubescent. 



•t- Indusium of a few broad segments, at first covering the sorus completely. 



4. W. obtusa (Spreng.) Torr. Frond broadly lanceolate, minutely glan- 

 dular-hairy (2-5 dm. high), pinnate or nearly bipinnate ; pinnae rather remote, 

 triangular-ovate or oblong (2-6 cm. long), bluntish, pinnately parted ; segments 

 oblong, obtuse, crenately toothed, the lower pinnatifid with toothed lobes ; veins 

 forked, and bearing the fruit dots on or below the minutely toothed lobes ; indu- 

 sium at length splitting into several spreading jagged lobes. — Rocky banks and 

 cliffs, " N. S.," and centr. Me. to Ga., and westw. Var. angtjsta Peck is a form 

 with very narrow fronds (35 cm. long and 4 cm. wide) and pinnae. — High- 

 lands, N.Y. 



•t- H- Indusium entirely concealed beneath the sorus, divided into very narrow 

 segments or reduced to mimite hairs. 



5. W. oregana D. C. Eaton. Glabrous; fronds bright green, soft in texture, 

 narrowly lance-oblong (12-23 mm. wide), bipiiinatifid, pinnae triangular-oblong, 

 obtuse ; the segments oblong or ovate, obtuse, crenate-serrulate, the teeth or 

 margin nearly always reflexed. — Limestone cliffs and ledges, Bic, Que. ; s. shore 

 of L. Superior (Rohhins), northw. and westw. 



6. W. Cathcartiana Kobinson. Finely glandular-puberulent ; fronds (2-3 

 dm. high) rather dull green, of firm texture, lanceolate (25-55 mm. broad), 

 bipinnatifid ; pinnae oblong, the lower distant ; segments usually separated by 

 wide sinuses, oblong, denticulate. {W. scopulina Man. ed. 6, not D C. 

 Eaton.) — Rocky river banks, w. Mich. {Wheeler), and n.e. Minn. {Miss Ellen 

 Cat he art.) 



7. W. scopulina D. C. Eaton. Loosely hispidulous with minute white hairs, 

 and finely glandular-puberulent; segments approximate, crenate-serrulate. — 

 Limestone cliffs ; Gasp6 Co., Que. ; S. Dak. ; Rocky Mts., etc. ; reported from 

 Minn, and n.w. la. 



17. DICKS6nIA L'H^r. 



Fruit dots small, globular, marginal, each placed on the apex of a free vein 

 or fork ; the sporangia borne on an elevated globular receptacle, inclosed in a 

 membranaceous cup-shaped indusium which is open at the top, and on the 

 outer side partly adherent to a reflexed toothlet of the frond. (Named for 

 James Dickson, an English cryptogamic botanist.^ 



