<1. POLYPODIUM. ^ d. PLEOPELTIS. D"^"^. PLEURIDinM. 04/ 



rib and edge, parallel to the main veins, immersed, prominent on the upper 

 surface. — Scarcely different from a small form Of P. heterocarpum, MeU. 

 Borneo. 



* (1726) P. Waletonianum, «. A. v. n.. Bull. D^p. Agr. I. N., 

 i908, XVIII, 23, tab. V. 



Rhizome creeping, stout, green, at length naked, the scales thin-membra- 

 naceous, yellowish, lanceolate, acuminate, erect, slightly hut distinctly crisped, 

 with the base rounded and peltate. Stipes ± remote, naked, + terete, firm, 

 erect, reddish or brownish-green in fresh material, 5— IS c.M. long, the fertile 

 fronds on the longest stipes. Fronds dimorphous. Barren fronds ovate-oblong 

 or sublanceolate, + 9—11 c.M. long, ± 4 — S c.M. broad below the middle, 

 narrowed towards the blunt or bluntish apex, the edge thickened and shallowly 

 crenate, the crenations broad, 1 to each main vein, straight or more commonly 

 slightly convex, the base rounded or cuneate, slightly decurrent upon the stipe. 

 Texture very coriaceous; surfaces naked; colour bright-green above, paler be- 

 neath in fresh material; costa prominent; main veins distinct, erecto-patent, 

 not quite reaching the margin ; areolae hidden, with free veinlets. Fertile 

 fronds linear, ±15 c.M. long, + 1 c.M. broad below the middle, narrowed 

 gradually towards the bluntish apex, the base suddenly cuneate; main veins 

 horizontally spreading, except the lowest pair, which is distinctly erecto-patent. 

 Sori large, medial, solitary between the main veins, oblong, perfectly parrallel 

 to the costa, the highest ones nearly round, the others gradually becom- 

 ing longer, the lowest + 4 — 6 X sis long as broad, + '/j c.M. long, all 

 .deeply immersed so as to form large, conspicuous papillae on the upper sur- 

 face of the frond. — The species bears the name of Dr. Th. Valeton, Director 

 of the Buitenzorg Herbarium. 



Java . {Preanger Regencies, y. A. v. R.). 



♦ (173) P. platypbyllum, *«»., Rac, Flor. Btz., I, 104; P. cras- 

 -sinervium, BL, Flor. Jav., II, 145, tab, LXI; Pleopellis platyphytla, Bedd., 

 Handb. Ind. Perns, Suppl., 94. 



Rhizome creeping, + woody, the scales dense, lanceolate, subulate-acumi- 

 nate, dark-brown or blackish. Stipes 2 — 3 c.M. apart, 3 — IB c.M. long, strong, 

 erect, canaliculate. Fronds 15 — 50 c.M. long, 4 — 12 c.M. broad, narrowed to 

 both ends, the point acute, the edge entire. Texture rigid, coriaceous, very 

 thick and firm; both surfaces naked, the upper densely covered with small 

 cretaceous dots; midrib prominent; main veins parallel, very distinct to 



