5) 



578 47. PTERIDIUM. 



Rhizome stout, wide-creeping, scaly. Stipes distant, 30 — 100 c.M. long, 

 strong, erect, naked, stramineous or brownish. Fronds deltoid to broad-lance- 

 olate, 60—200 c.M. long or longer. 30—60 c.M. or more broad. Uppermost 

 pinnae simple, the next pinnatifid, the following pinnate, the lowest largest, 

 3-pinnatifid. Ultimate segments linear-oblong, 1 — 2*/, c-M. long, 3 — 5 

 m.M. broad, numerous, close. Texture coriaceous; rachis and surfaces naked; 

 veins close, conspicuous, often 1 — 2 X forked. 



Var. lannginosuiu : Fronds pubescent or silky-tomentose beneath ; 

 pinnulae more regularly pinnatifid. 



Vai*. esculentum : Rhizome fibrillose or hairy; ultimate segments 

 more distant, connected by their suddenly dilated, decurrent bases. 



Cosmopolitan, chiefly northern; — var. lanugiuosum: chiefly tropical; — 

 var. esculentum: Borneo, New Guinea; Australia. 



4^. LiOMAJES.1.^, WiUdenoM}. 



Sori linear, continuous, on a broad receptacle, parallel to the margin, at 

 length filling up the whole space between the midrib and the margin. In- 

 dusium linear, ' conoioting of the modified, reflexed margin of the frond (*). 



Rhizome or caudex erect. Stipes not articulate, purveyed with 2 stout 

 and 1 to several finer vascular strands placed altogether in a circle, the stout 

 ones abreast at the inner (upper) side. Fronds simple to 2-pinnatifid, di- 

 morphous, the fertile ones with the pinnae narrowly linear; veins free, 

 but united by the receptacle in the fertile segments. Hk. Bk., Syn. Fil., 

 tab. Ill, fig. 33; Diels, in Engl. & Prantl, Nat. Pfl.Fam., I*, fig. 131 (as 

 Blechnum, § Lomaria). 



Tropical and extra-tropical. 



a. Barren fronds simple, pinnatifid or pinnate; lobes or pinnae suddenly dilated 



and decurrent at the base, adnate to the rachis. (1) L. Patersoni. 



« 

 a.a. Barren fronds pinnate; pinnae slightly dilated, but not decurrent at the base, 



adnate to the rachis. (2) L. vulcaaica. 



a.a.a. Barren fronds pinnate; lower pinnae truncate or rounded at the base; not 



adnate to the rachis. 



(*) See also under Stenochlaena. 



