14 POLYPODIACEAE 



16. ANCHISTEA Presl. 



Coarse swamp ferns. Leaves uniform, Sori superficial, borne upon transverse 

 veins forming', the outer sides of a single series of elongated areoles next to the 

 midribs of the leaflets and segments; veins elsewhere free. Indusia extrorse. 



1. Anchistea Virginica (L.) Presl. Rootstoek creeping, slender. Petioles stout, 

 3-9 dm. long, dark-colored and shining below; blades oblong-lanceolate to ovate- 

 lanceolate, acute, 3-6 dm. long, 15-22 cm. broad, pinnate, the leaflets linear-lanceolate, 

 oblique, glabrous, sessile, acuminate, 7-15 cm. long, deeply pinnatifid, the segments 

 ovate or oblong, close, obtuse, serrulate. [Woodwardia Virginica (L.) J. E. Smith.] 



In swamps and meadows, Nova Scotia to Ontario, Michigan, Florida, Louisiana and 

 Arkansas. Also in Bermuda. 



17. ASPLENIUM L. 



Plants of various habit and habitat. Leaves usually tufted: blades simple to 

 several times pinnate or pinnatifid, usually uniform, leathery to very delicately mem- 

 branous, with free veins. Sori oblong to linear, oblique to the midrib or rachis. 

 Indusia opening along the side nearest the midrib. SPLEENWOBT. 



Leaf-blades simple. 1. A. serratum. 



Leaf-blades 1 to several times pinnate or pinnatifid. 

 Leaf-blades pinnatifid or simply pinnate. 



Leaf-blades pinnatifid, or pinnate only below. 



Petioles blackish below, green above; leaf -segments normally 



rounded. 2. A. pinnatifidum. 



Petioles purplish-brown throughout; leaf segments usually 



acutish to acuminate. 3. A. ebenoides. 



Leaf-blades simply pinnate. 



Rachis chestnut-brown or darker, shining. 



Leaflets not auriculate. 4. A. Trichomanes. 



Leaflets more or less auriculate. 



Fertile leaves erect, the sterile ones short, rosulate. 5. A. platyneuron. 



Fertile and sterile leaves similar, erect or ascending. 



Leaf-tissue leathery; sori short, medial or supermedial. 6. A. resilient, 

 Leaf -tissue membranous; sori longer, near the midrib. 7. A. muticum. 

 Rachis greenish, not lustrous. 



Leaflets nearly equilateral at the truncate or obtuse base, 



the margins entire or crenulate. 8. A. pycnocarpon. 



Leaflets inequilateral at the base; narrowly cuneate or 



excised below, the margins dentate to crenate-serrate. 



Leaf -blades usually deltoid or deltoid-ovate, acuminate. 9. A. abscissum. 



Leaf-blades oblong to linear, obtuse or acutish. 10. A. dentatum 



Leaf-blades 2 3-pinnatifid or -pinnate. 

 Leafy-tissue leathery. 



Petioles green; leaf-blades rhombic to deltoid-ovate, the veins 



flabellate. 11. A. Ruta-muraria. 



Petioles dark below: leaf-blades deltoid-lanceolate, or broadly so. 12. A. montanum. 

 Leaf-tissue herbaceous or membranous. 



Petioles and most of the rachis chestnut-brown, shining. 13. A. Bradley i. 



Petioles greenish to brownish, not shining. 



Leaf -blades bipinnatifid (see, however, no. 14). 



Blades oblong-lanceolate to deltoid^vate, acuminate. 14. A. erosum. 



Blades narrowly pblanceolate to linear-oblong, acutish. 15. A. Biscay neanum. 

 Leaf-blades at least bipinnate. 



Petioles usually very short; leaf-blades linear-oblanceolate. 16. A. verecundum. 

 Petioles longer; leaf -blades larger, oblong or lanceolate 



to ovate- or oblong-lanceolate. 

 Leaflets spreading, their main divisions truncate above, 



excised below; segments several pairs, spreading. 17. A. cristatum. 

 Leaflets ascending, their divisions narrowly cuneate; 



segments fewer, more oblique, relatively coarser. 18. A. Curtissii. 



1. Asplenium serratum L. Leaves in a crown from a stout erect rootstoek ; 

 blades linear-oblanceolate, 4-7 dm. long, crenulate or irregularly serrulate, somewhat 

 leathery; midrib keeled, often blackish purple beneath; veins close, once-forked: sori 

 elongated, following the veins of the upper half of the blade from near the midrib 

 half way to the margins. 



In swamps, peninsular Florida. Also in tropical America. 



2. Asplenium pinnatifidum Nutt. Rootstoek short, chaffy. Leaves tufted ; 

 petioles 5-12 cm. long, blackish and somewhat chaffy below, green above; blades 

 broadly lanceolate, 7-25 cm. long, firm, tapering to a long narrow tip, pinnatifid or 

 the lower parts pinnate ; one or more lower segments sometimes prolonged like the apex. 



On rocks, New Jersey to Illinois and Arkansas, and in the mountains to Georgia. 



3. Asplenium ebenoides R. R. Scott. Rootstoek short, chaffy. Leaves tufted; 

 petioles purplish brown, 4-17 cm. long; blades deltoid-lanceolate, variable, 8-25 cm. 



