Cyathea. | FILICES. 23 
(are. 5.) 
1. C. dealbata “Swartz Syn. Fil. (1806) 140.—Trunk 10-30 ft. high, 
seldom more, 9-18in. diam. at the base, clothed above the middle with the 
short light-brown bases of the old stipites. Fronds numerous, horizontally 
spreading, 6-12 ft. long, 2-4 ft. broad, 2-3-pinnate, subcoriaceous, green or 
yellow-green above, pure-white beneath from a coating of deciduous powder. 
Stipes rather slender, slightly asperous, clothed at the base with shining 
dark-brown linear scales, elsewhere (together with the rhachis and costae). 
more or less covered with yellow-brown deciduous tomentum, becoming 
almost glabrous when old. Primary pinnae 1-14 ft. long, oblong, acuminate ; 
secondary, 2-4 in., linear-lanceolate, acuminate or almost caudate, deeply 
pinnatifid or pinnate towards the base. Segments or pinnules 1-4 in. long, 
linear-oblong, acute or subacute, more or less faleate, serrate. Sori small, 
globose, copious, but often confined to the lower half of the segments. 
Indusium small, membranous, only covering the sorus in a very early stage, 
persistent at the base as a shallow cup.—ad. Rich. Fl. Nouv. Zel. (1832) 
77, t. 10. A. Cunn. Precur. (1836) n. 226; Raoul Choix (1846) 38; Hook. 
Sp. Hil. 1 (1846) 27; Hook. f. Fl. Nov. Zel. ti (1855) 7; Handb. N.Z. FI. 
(1864) 349; Hook. and Bak. Syn. Fil. (1873) 26; Thoms. N.Z. Ferns (1882) 
28; Mield N.Z. Ferns (1890) 45; Cheesem. Man. N.Z. Fl. (1906) 948. 
(4) Hemitelia falcifelia Col. Trans. N.Z. Inst.xxiv. (1892) 394. Polypodium 
dealbatum Forst. f. Prodr. (1786) n. 454. 
NortH anp SourH Istanps, CuatHam IsuaAnps: Abundant in woods from the 
North Cape to Foveaux Strait. Sea-level to 2500 ft Ponga ; Silver Tree-fern. 
Perhaps the most generally distributed of the New Zealand tree-ferns. It can 
usually be identified at a glance by the milk-white under-surface of the fronds, although 
individual specimens are occasionally seen in which the under-surface is obscurely 
glaucous or even quite green. Very young plants are always green beneath; the white 
first appearing in irregular patches, giving the under-surface a curious piebald appear- 
ance. Outside New Zealand it occurs in Lord Howe Island, and a barren plant collected 
at Penang is assumed to be the same. 
2. €, medullaris Swartz Syn. Fil. (1806) 140.—Trunk 20-50 ft. high 
or even more, in old plants furnished at the base with a hard and thick 
conical buttress formed of densely compacted aerial rootlets, sometimes 
extending for several feet up the trunk, and 1-23 ft. diam. at the foot; 
trunk proper rather slender for its height, black, marked with the hexagonal 
scars of the old stipites, and at the very top rough with the remains of the 
stipites. Fronds numerous, 20-30, curving, 8-20 ft. long, 3-5 ft. broad, 
2-3-pinnate, coriaceous, dark-green above, paler beneath. Stipes stout, 
clothed at the base with copious black linear scales, and together with the 
rhachis more or less covered with scattered tubercles. Primary pinnae 
13-8 ft. long, oblong-lanceolate, acuminate ; secondary 4-6 in. long, #-J1 in. 
broad, linear-lanceolate to linear-oblong, acuminate, pinnate below, pinnatifid 
above, costae more or less clothed with tawny silky hairs or slabrous. 
Pinnules or segments about 4in. long, +,-$in. broad, linear or linear- 
oblong, obtuse, faleate ; the fertile ones deepiy crenate-serrate or lobulate, 
sometimes pinnatifid; the barren ones broader, crenate-serrate or almost 
entire; costules usually with pale ciliated scales beneath. Sori very 
numerous, one to each lobe of the pinnule. Indusium brown, membranous, 
splitting into 2-4 irregular lobes.—A. Rich. Fl. Nouv. Zel. (1832) 78; 
A. Cunn. Precur. (1836) n. 227; Raoul Choir (1846) 388; Hook. Sp. Fil. i 
(1846) 26; Hook. f. Fl. Nov, Zel. ii (1855) 7; Handb. N.Z. Fl. (1864) 349; 
Hook. and Bak, Syn. Fil. (1873) 25; Thoms. N.Z. Ferns (1882) 28; Field 
N.Z. Ferns (1890) 42, t. 9, f..3; Cheesem. Man. N.Z. Fl. (1906) 948. 
