948 FILICES. [ Cyathea. 
** Under-surface of frond green. 
Trunk 20-50ft. Fronds 8-20ft., coriaceous; stipes and 
rhachis conspicuously muricate beneath. Fertile seg- 
ments lobulate or pinnatifid ye ne Be 
Trunk 20-40 ft. Fronds 6-18 ft., not so coriaceous ; stipes 
and rhachis rough but hardly muricate, clothed with 
yellow-brown tomentum. Fertile segments obscurely 
serrate, not lobulate ae ays =F Fs 
Trunk 8-20ft. Fronds 6-10ft., almost membranous; 
stipes and rhachis slightly asperous, clothed with 
strigose hairs above. Fertile segments lobulate or 
pinnatifid .. 36 a ae Le .. 4. C.Cunninghami, 
2. C. medullaris. 
3. C. Milne. 
1. CG. dealbata, Swartz, Syn. Fil. 140, 356.—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, 2-8- 
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 costz) more 
or less covered with yellow-brown deciduous tomentum, becoming 
almost glabrous when old. Primary pinne 1-1} it. long, oblong, 
acuminate; secondary 2-4 in., linear-lanceolate, acuminate or 
almost caudate, deeply pinnatifid or pinnate towards the base. 
Segments or pinnules $-} 1n. long, linear-oblong, acute or sub- 
acute, more or less falcate, 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.—A. Rich. Fl. Nouv. Zel. 77, 
t. 10; A. Cunn. Precur. n. 226; Raoul, Choix, 38; Hook. Sp. Fu. 
i. 27; Hook. f. Fl. Nov. Zel. ii. 7; Handb. N.Z. Fl. 349; Hook. and 
Bak. Syn. Fil. 26; Thoms. N.Z. Ferns, 28; Field, N.Z. Ferns, 45, 
t. 10, f.2. OC. tricolor, Col. in Trans. N.Z. Inst. xv. (1883) 304. 
(?) Hemitelia falciloba, Col. in Trans. N.Z. Inst. xxiv. (1892) 394. 
Polypodium dealbatum, Forst. Prodr. n. 404. 
Norru anp SourH Is~LAnDs, CHATHAM IsLANDS: Abundant in woods from 
the North Cape to Foveaux Strait. Sea-level to 2000ft.  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 appearance. Outside New Zealand it occurs in Lord 
Howe Island, and a barren plant collected at Penang is assumed to be the same. 
2. CG. medullaris, Swartz, Syn. Fil. 140, 366.—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 root- 
