FiLiCES. (ferns.) 597 



hidden by the ripened sporangia. — Rocky places, North Carolina, Tennessee, 

 and northward. — Fronds 6'- 16' higii. 



17. DICKSONIA, L'llcr. § SITOLOBIUM, Desv. 



Fruit-dots small, globular, terminal on the free veins ; sporangia on an ele- 

 vated reeeptdde in a thin eup-shaped invoiu*rc which is partly adherent to a 

 reflexed lobule of the frond. Fronds large, 2-3-pinnatc, from a creeping root- 

 stock. — DiCKSONiA proper has large two-lipped involucres, of a firmer texture, 

 and several species have an arborescent caudex. 



1. D. punctilobula, Kunze. Fronds delicate, slightly glandular-|)ubcs- 

 cent, as is tiie racliis, hmceolate-acuminate, 2 - .3-pinnate ; pinna; numerous; 

 pinnules oblong-ovate, closely placed, obtuse, pinnately incised or pinnatilid ; 

 the divisions obtusely serrate, each one bearing a minute fruit-dot at tlic upper 

 margin. — Moist shady woods in the upper part of North Carolina, Tennessee, 

 and northward. — Rootstock slender, extensively creeping. Fronds 2° - 3° high, 

 when crushed returning a pleasant odor. 



18. TRICHOMANES, L. 



Sporangia -with a transverse entire ring, arranged on the lower part of a 

 cylindrical, filiform, often elongated receptacle : involucres marginal, funnel- 

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

 thin and pellucid. 



1. T. Petersii, Gray. Veiy small, with entangled filiform tomentosc root- 

 stocks ; fronds oblong-lanceolate or obovate, entire or variously pinnatilid, nar- 

 rowed into a slender stipe nearly as long as the frond, the younger ones witli a 

 few black forked hairs along the margin ; veins forked, pinnate from the midrib ; 

 involucre solitary, terminal, funnel-shaped, the mouth expanded and slightly 

 two-lipped, receptacle included. — On the face of a sandstone rock, sprinkled 

 from a waterfall, Hancock Co., Alabama, T. M. Peters. Also among some 

 Mosses sent from Pensacola, Florida. — Fronds less than an inch high. 



2. T. radicans, Swartz? Fronds pellucid, with a loose roundish arcola- 

 tion, on a short broadly winged stipe, lanceolate or ovate-lanceolate, bipinnatifid ; 

 pinna; ovate or deltoid-ovate, obtuse, the upper side of the base parallel and 

 apprcssed to the winged rachis, the lower side cuneate ; divisions toothed or 

 divided into linear lobes ; involucres terminal on short lobes of the pinna;, 

 tubular-funnel-shaped, margined, at the mouth truncate and slightly two-lipped ; 

 receptacle exserted a little or very much. (T. Boschianum, Sturm.) — Hancock 

 County, Alabama, Peters, Beaumont. Cumberland Mountains, Eastern Tennes- 

 see, Rev. Dr. Curtis. — Rootstock slender, creeping, tomentose with black hairs. 

 Fronds 4'-8' high, 12"- 18" wide. 



19. LYGODIUM, Swartz. Climbing Ferk. 



Sporangia beneath ovate hood-shaped imbricated indusia, in a double row on 

 narrow divisions of the fronds, attached laterally, ovate, with a many-rayed api- 



