FERN FAMILY 1049 



2. P. glabella Mett. Scales of rhizome rust-colored; fronds tufted, 2.5-16.7 

 cm. long; stipes slender; blades ovate to oblong or ovate-lanceolate; pinnae simple 

 and 0.7-1.9 cm. long, or commonly the lower pinnately trifoliate, those of the 

 lowermost one or two pairs rarely with 4 or 5 segments; segments oblong to 

 lanceolate or the smaller ovate-oblong or suboval, obtuse or abruptly acute; 

 branches of mid veins mostly once or twice forked; indusia entire or slightly 

 erose. P. pumila Rydb. P. atropurpurea occidentalis A. Nels. P. atropurpurea 

 Bushii Macoun. On dry rocks: Ariz. Wyo. Wash. Minn. Ark. Kan. 

 N.Y. Vt. B.C. Undoubtedly of wider range, especially in the north. Plain 

 Mont. 



3. P. atropurpurea Link. Scales of rhizome fulvous rust-colored; fronds 

 tufted, 2.5-41.7 cm. long; stipes wiry; blades lanceolate or ovate-lanceolate, pin- 

 nate or usually bipinnate below; sterile segments commonly suboval; fertile 

 segments mostly linear or sublinear, sometimes auricled, obtuse or acute; branches 

 of mid veins mostly about twice forked; indusia entire or slightly erose. On dry 

 rocks, particularly limestone: "N.H." "R.I." Ga. nw Mex. Ariz. S.D.; 

 "B.C." "Athabasca." 



4. P. mucronata D. C. Eat. Scales of rhizome black-striped at center, with 

 light tawny margins; fronds tufted, 8-60 cm. long; stipes and rachises dark 

 mahogany-colored or purplish black, smooth; segments sessile or subsessile, the 

 sterile roundish oval, sometimes subcordate at base, the fertile linear-oblong, 

 with strongly revolute margins. P. Wrightiana Hook. P. longimucronata 

 Hook. P. truncata Goodding. On rocks: Tex. Kans. Calif. L. Calif. Son. 



14. CHEILANTHES Sw. LIP-FERN. 



Small ferns with compound, usually chaffy or hairy fronds. Indusium 

 formed of the reflexed margins of the subdivisions, roundish and distinct or con- 

 tinuous. Sori roundish and distinct or more or less confluent, borne on the 

 thickened apices of free veins. 



Blades scaly, not tomentose. 1. C. Fendleri. 



Blades tomentose beneath, with or without scales. 



Blades without scales. 2. C. Feei. 



Blades having scales. 



Ultimate segments oblong-oval ; upper surface at first scantily webby, soon glabrous. 



3. C. (jracillima. 

 Ultimate segments rounded, narrowed toward base; upper surface tomentose. 



4. C. Eatoni. 



1. C. Fendleri D. C. Eat. Rhizome creepy, chaffy with bright tawny scales 

 without dark centers; fronds mostly scattered, 6-25 cm. long; blades ovate- 

 lanceolate, tripinnate; stipes and primary rachises brown, chaffy with mostly 

 slender scales; secondary and tertiary rachises chaffy, the scales imbricate, bright 

 brown, usually white-margined, broadly ovate, entire or subentire, not ciliate or 

 very sparingly ciliate at base; ultimate segments minute, subglobose, entire, or. 

 obovate and 2-3-lobed, smooth above, commonly with a single broad scale at 

 the center beneath; indusia formed of the much recurved margins. Dry rocks: 

 Colo. "w Tex." Ariz. Submont.Mont. 



2. C. Feei Moore. Scales of the rhizome cinnamon-brown, mostly black- 

 striped at center; fronds tufted, 5-16 cm. long; stipes and rachises dark brown 

 or blackish; blades ovate-lanceolate, tripinnate or tripinnatifid, rarely bipinnate; 

 lower pinnae deltoid, those above oblong-ovate; ultimate segments minute, the 

 apical one slightly the largest, their lower surfaces densely tomentose; hairs 

 whitish brown, soft, matted, flattened, jointed; indusium subcontinuous around 

 the segment, formed of its scarcely altered margin. C. lanuginosa Nutt. On or 

 among rocks: B.C. Minn. 111. Ark. Ariz.; Mex. Plain Submont. 



3. C. gracillima D. C. Eat. Scales of the rhizome dark rusty brown with 

 darker, not black, centers; fronds tufted, 4-24 cm. long; stipes and primary 

 rachises dark brown or blackish; blades narrowly ovate-lanceolate, bipinnate or 

 sometimes subtripinnate; tomentum consisting of scale-like branching hairs; 

 rachises chaffy, with slender scales ciliate at base; indusium continuous around 

 the segment. On rocks: B.C. Mont. Ida. Calif.; Mex. 



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