POLYPODIACEAE. 



VOL. I. 



ii. Asplenium Bradley! D. C. Eaton. Bradley's 



Spleenwort. Fig. 68. 

 A. Bradleyi D. C. Eaton, Bull. Torr. Club 4:11. 1873. 



Rootstock short, covered with dark narrow scales. 

 Stipes tufted, slender, 2'-^' long, dark chestnut-brown 

 throughout, shining ; blades oblong-lanceolate to oblong, 

 acuminate or scarcely narrowed at the base, pinnate, 

 with 8-12 pairs of short-stalked mostly oblong-ovate, 

 obtuse pinnae, the lower pinnae often unequally deltoid, 

 pinnatifid or pinnate with oblong obtuse lobes or pin- 

 nules, these toothed at the apex, the upper pinnatifid 

 with dentate or nearly entire lobes ; rachis brown or 

 greenish above ; sori short, borne near the midveins ; 

 indusia membranous, persistent. 



On rocks, preferring limestone. New York to Georgia 

 Alabama, Arkansas and Missouri. Local. July-Sept. 



13. ATHYRIUM Roth, Romer's Arch. Bot. 

 2 1 : 105. 1799. 



Medium-sized or large ferns with greenish succulent stipes and i-3-pinnate or pinnatifid 

 blades; veins free; scales of the rootstock delicate, of thin-walled cells. Sori usually curved, 

 oblong to linear-oblong, or crossing the vein and recurved, sometimes unequally hippocrepi- , 

 form, rarely roundish. Indusia shaped like the sorus, attached as in Asplenium, subentire to 

 fimbriate, rarely vestigial and concealed. [Greek, shieldless, of doubtful application.] 



A genus of about 85 species, mainly of tropical regions. A. cyclosonnn occurs in western 

 North America. Type species : Athyrium Filix-foemina (L.) Roth. 



Blades bipinnatifid ; segments lightly crenate-serrate. i. A. thelypteroides. 



Blades bipinnate ; pinnules variously incised or deeply serrate. 2. A. Filix-foemina. 



I. Athyrium thelypteroides (Michx.) Desv. 

 Silvery Spleenwort. Fig. 69. 



Asplenium acrostichoides Sw. Schrad. Journ. Bot. 1800* : 



54. 1801. Not Athyrium acrostichoideum Bory, 1836. 

 Asplenium thelypteroides Michx. Fl. Bor. Am. 2: 265. 1803. 

 Athyrium thelypteroides Desv. Mem. Soc. Linn. Paris 6 : 



266. 1827. 



Rootstock slender, sinuous, creeping. Stipes 8'-i6' 

 long, straw-colored, somewhat chaffy below, at least 

 when young; blades lanceolate, oblong-lanceolate, or 

 ovate-oblong, i-3 long, 6'-i2' wide, acute or acumi- 

 nate, narrowed to the base, very deeply bipinnatifid ; 

 pinnae linear-lanceolate to oblong-lanceolate, sessile, 

 acuminate, deeply pinnatifid into numerous oblong 

 obtuse or subacute lightly serrate-crenate segments; 

 sori crowded, curved or straight, the lower often double; 

 indusium light-colored and shining when young. 



In rich moist woods, Nova Scotia to Minnesota, Mis- 

 souri and Georgia. Ascends to 5000 ft. in Virginia. 

 Closely related forms occur in eastern Asia. Aug.-Oct. 



2. Athyrium Filix-foemina (L.) Roth. 

 Lady-fern. Female-fern. Fig. 70. 



Polypodium Filix-foemina L. Sp. PI. 1090. 1753. 

 Asplenium Filix-foemina Bernh. Schrad. Neues Journ. 



Bot. i 2 : 26. 1806. 

 A. Filix-foemina Roth, Romer's Arch. 2 1 : 106. 1799. 



Rootstock creeping or ascending, slender for the 

 size of the plant. Stipes tufted, 6'-i2' long, straw- 

 colored, brownish or reddish ; blades broadly oblong- 

 ovate to oblong-lanceolate, acuminate, i-3 long, 

 2-pinnate; pinnae lanceolate, acuminate, short-stalked 

 or the upper ones sessile, 4'-8' long; pinnules oblong- 

 lanceolate to broadly elliptical, incised or serrate, the 

 lobes or teeth often again toothed, those toward the 

 ends of the pinnae confluent; sori short; indusia 

 straight or curved, sometimes horseshoe-shaped. 



In woods and thickets, Newfoundland to British Co- 

 lumbia, the Gulf states, and California. Ascends to 

 6000 ft. in North Carolina, and to 2000 ft. in Vermont. 

 Europe and Asia. June-Aug. Backache-brake. 



