122 OUR NATIVE FERNS AND THEIR ALLIES. 



Hook., D. punctilobula Kunzej Nephrodtum punctilobulum 

 Michx., Aspidium punctilobulum Torr.) Canada to Tennessee. 



XXVI. TRICHOMANES Sm. FILMY-FERN. 



Sori marginal, terminating a vein, more or less sunken in 

 the frond. Sporangia sessile on the lower part of a cylindrical, 

 filiform, often elongated receptacle. Indusia tubular or funnel- 

 shaped, entire or two-lipped at the mouth. Fronds delicate, 

 pellucid. Name from Gr. rpixouaveS, the name of some fern, 

 from rpi'x, hair, and juairouat, producing frenzy, alluding to 

 some supposed property. A tropical and temperate genus con- 

 taining nearly 100 species. 



EUTRICHOMANES. 



1. T. Petersil Gray. Stipes i" 2" long ; fronds 3" 10" 

 long, i" 2" broad, oblong-lanceolate or obovate, entire or vari- 

 ously pinnatifid, the younger ones with a few black hairs along 

 the margins; indusium solitary, terminal, funnel-shaped, the 

 mouth expanded and slightly two-lipped, the receptacle in- 

 cluded. Winston County, Alabama (Peters). 



2. T. radicans Swz. Rootstock wiry, tomentose ; stipes 

 ascending, i' 3' long, naked or nearly so, usually broadly 

 winged; fronds 2' 8' long, i' 1' wide, lanceolate or ovate- 

 lanceolate, bipinnatifid ; pinnae ovate, obtuse, the upper side of 

 the base parallel and appressed to the winged rachis, the lower 

 side cuneate ; divisions toothed or divided into linear lobes ; 

 indusia terminal on short lobes, tubular or funnel-shaped, the 

 mouth slightly two-lipped; receptacle exserted little or very 

 much. (T. spectosum Willd.) Alabama, Tennessee, Kentucky. 



XXVII. LYGODIUM Swz. CLIMBING-FERN. 



Sporangia ovoid, solitary or occasionally in pairs, in the 

 axils of large imbricated scale-like indusia, which are fixed by 

 their broad bases to short oblique veinlets. Fronds scandent, 

 twining, bearing stalked and variously lobed divisions in pairs. 

 Veins mostly free. Name from Gr. XvyGoSrjS, flexible, alluding to 

 the scandent stems. Includes 16 species. 



EULYGODIUM. 



i. L. palmatum Swz. Stipes slender, flexile, and twin- 

 ing; fronds i 3 long, the short alternate branches or peti- 



