28 



POLYPODIACEAE. 



VOL. I. 



5. Asplenium Trichomanes L. Maiden hair Spleenwort. Fig. 62. 



Asplenium Trichomanes L. Sp. PI. 1080. 1753. 



Rootstock short, nearly erect, chaffy with blackish 

 scales. Stipes densely tufted, commonly numerous, 

 l'-2i' long, purplish-brown and shining; blades linear, 

 often somewhat reduced toward the base, 3'-8' long, 

 4"~9" wide, rather rigid, once pinnate, evergreen, the 

 rachis dark brownish ; pinnae mostly oval or roundish- 

 oblong, inequilateral, partly opposite, partly alternate, 

 or nearly all opposite, cuneate at the base, the margins 

 slightly crenate; lower pinnae smaller and relatively 

 broader, farther apart, often fan-shaped in outline; sori 

 3-6 pairs, short, commonly confluent at maturity; spo- 

 ranges dark brown. 



On rocks, preferring limestone, throughout nearly the 

 whole of North America north of Mexico except the 

 extreme north. Ascends to 2500 ft. in Vermont. Also 

 in Europe and Asia. July-Sept. Called also Wall- or 

 dwarf-spleenwort ; water-wort, english maiden-hair. 



6. Asplenium viride Huds. Green Spleenwort. 



Fig. 63. 



Asplenium viride Huds. Fl. Angl. 385. 1762. 



Rootstock stout, creeping, chaffy with brown nerve- 

 less scales, the leaves usually borne in dense tufts. 

 Stipes numerous, stout or sometimes very slender, 

 brownish below, green above, i'-3' long; blades linear- 

 lanceolate, 2'-S' long, 4"-io" wide, once pinnate, pale 

 green, soft-herbaceous or almost membranous; rachis 

 green ; pinnae 12-20 pairs, roundish-ovate or rhombic, 

 deeply crenate, obtuse, unequal-sided, broadly cuneate 

 at the base, the lower side obliquely truncate ; sori near 

 the midvein, oblong, usually numerous and confluent, 

 or sometimes fewer and somewhat apart. 



On rocks, Quebec and New Brunswick to Alaska, south 

 to Washington, Wyoming, and the Green Mountains of 

 Vermont. Also in Europe and Asia. Summer. 



7. Asplenium pycnocarpon Spreng. Narrow-leaved Spleenwort. Fig. 64. 



Asplenium angustifolium Michx. Fl. Bor. Am. 2: 265. 



1803. Not Jacq. 1786. 



Asplenium pycnocarpon Spreng. Anleit. 3: 112. 1804. 

 Athyrium pycnocarpon Tidestrom, Elys. Marianum 36. 



1906. 



Rootstock stout, creeping, rooting along its whole 

 length. Stipes clustered, naked, dark brown at the 

 base, green and somewhat fleshy above, S'-is' long; 

 blades lanceolate to lanceolate-ovate, i-2i> long, 

 once pinnate, glabrous, membranous ; pinnae 20-30 

 pairs, 2'-5' long, short-stalked, lightly crenulate, 

 linear-oblong, attenuate, flaccid, obtuse or broadly 

 cuneate. at the base, those of the fertile blades usually 

 smaller and considerably narrower than those of the 

 fertile, often falcate; sori 20-30 pairs, close, linear, 

 slightly curved, oblique; indusium firm, convex, con- 

 cealed by the strongly confluent sori at maturity. 



In moist woods and shaded ravines, Quebec to Wis- 

 consin, south to Georgia, Alabama, Missouri and Kan- 

 sas. Ascends to 1700 ft. in the Aclirondacks and to 

 2300 in the Catskills. Aug. Swamp-spleenwort. 



