Flora of New Zealand Series

Polypodium dealbatum Forst. f. Prodr. 1786, 83.

Ponga.

Caudex up to 10 m. tall with basal diam. 45 cm., us. smaller; bases of stipites long-persistent. Stipes rather stout, ± 4 cm. diam. near base; paleae shining dark brown, c. 5 cm. long; hairs yellow-brown, cop., deciduous. Lamina up to 3 × 1 m. or more, 2-3-pinnate; subcoriac., attenuate; dark green above. Juvenile plants with lamina pale green below; subsequent fronds becoming patched with white to glaucous bloom below; adult plants with lamina almost completely white or glaucous below. Primary pinnae 30-50 cm. long, oblong-acuminate; secondary up to 10 cm. or more, oblong-lanceolate, attenuate. Tertiary pinnae or segs up to 15 mm. long, subfalcate, subacute to acute, crenate-serrate in upper half, margins slightly recurved, veinlets free. Sori us. cop., globose, c. 1 mm. diam. (may be present on only partly dealbate fronds). Indusium thin, at first covering sorus, persisting as a shallow cup.

DIST.: N., S., Ch. Lowland to montane forest throughout, also occurs in shrubland.

Also Lord Howe Id.

Domin in Bibl. Bot. 85, 1915, 27, recognized C. tricolor Col. in T.N.Z.I. 15, 1883, 304, as a var. of C. dealbata. Colenso's material came from: "Deep forests (Seventy-mile Bush) on eastern outlying spurs of the Ruahine Mountain Range, between Norsewood and Danneverke villages; April 1882." His long description includes: "stipes very stout, 3-31/2 inches girth at base . . . peculiar bluish-white below,· prickly with small fine sharp black prickles . . . pinnules finely and very beautifully acuminate, apices finely regularly serrated at tip . . . involucre, a shallow circular cup, margin entire, rarely breaking up." He stresses the bluish tint of the lower surface of the lamina, and the manner of drooping of the frond: "firstly, its fronds outwards and downwards; secondly their pinnae downwards and inwards towards the main rhachis; thirdly the pinnules downwards and inwards towards the secondary rhachises; and then, fourthly, the very fruiting segments themselves conniving inwardly." The type in W (Norsewood) consists of one complete and four partial pinnae. The drooping features are not revealed; the colour is not markedly bluish. Cheeseman (Man. N. Z. Fl. 1906, 948) treats the name as a synonym of C. dealbata, but omits it altogether in the second, 1925, edition.

Hemitelia falciloba Col. in T.N.Z.I. 24, 1892, 394, is transferred to Cyathea by Domin Pterid. 1929, 264. Cheeseman (Man. N.Z. Fl. 1925, 23) considers it (misprinted falcifolia) as synonymous with C. dealbata. The material, "partial and young," was gathered from two plants, later destroyed by fire: "On the sides of a precipitous gully overhanging a small streamlet, in a forest south of Dannevirke, County of Waipawa; January, 1889: W.C." Colenso's description includes: "Fronds spreading, bipinnate, submembranous, brownish-green above, pale (sometimes nearly white) below with minute shining specks widely dispersed . . . lobes alternate, remote, free falcate, semisubulate, tips acuminate, acute, margins recurved, plain, slightly serrulate towards apex. Veins pinnate, distant, very clear, veinlets forked and triple . . . Involucre a very small concave greyish scale on the posterior side." His description is not easy to follow, nor do the type specimens in W altogether fit. The material consists of four partial pinnae (2 sterile, 2 fertile). Secondary sterile pinnae firm, up to 8 × 2 cm., subsessile, lanceolate-oblong, acuminate, now dull brown above, pale brown below, without evidence of bloom; pinnules alt., confluent at base, about oblong, widened slightly at base, acute to acuminate at apex, ± falcate, margins recurved, up to 1 cm. long; venation as described by Colenso. Secondary fertile pinnae less firm, up to 5 cm. × 7 mm., narrow lanceolate-oblong, acuminate; colour similar; pinnules alt., confluent to distinct at base, similar to those of sterile pinnae but not over 5 × 2 mm. Indusium incomplete to vestigial. The only minute shining specks I can find are those of insect eggs. The specimens show but little resemblance to C. dealbata, and their status deserves further study.