Flora of New Zealand Series

Referred to the very closely allied D. antarctica R. Br. by Hooker in Fl. N.Z. 2, 1855, 9.

Kuripaka.

Type locality: "Banks of rivers, in the Te Wai iti District." Type: Colenso W. Endemic.

Spreading rhizomes not developed. Caudex up to 6 m. tall, densely invested with matted rootlets so that the diam. is up to 6 dm. or more in the lower part. Dead fronds long persistent, pendent. Stipes very short, densely clad near base with soft, light red-brown hairs: rhachides clad in soft pale brown hairs, glabrate in age. Lamina about lanceolate, 2-3-pinnate, up to 2 m. long, coriac. Primary pinnae 15-30 cm. long, oblong-lanceolate, acuminate; secondary up to 5 cm. long, rather close-set. Pinnules c. 5 mm. long, acute, widened and confluent at base. Fertile lobes rounded, strongly concavo-convex, each bearing a sorus; barren lobes, shallowly concavo-convex, subfalcate, acute, toothed or not. Indusium submembr., concavo-convex.

DIST.: N., S., Ch. Lowland forest from 37º 30' southwards.

Colenso made a close study of Dicksonia in N.Z., and his remaining spp. placed under D. fibrosa by Cheeseman (Man. N.Z. Fl. 1925, 21) deserve fresh study in the field. D. intermedia Col. ex Hook. et Baker Synopsis Fil. 1873, 461, is represented in W by a small piece of rhachis with two pinnae, and two separate pinnae 21 cm. long. The material does not show any clear difference from D. fibrosa. D. sparrmanniana Col. in T.N.Z.I. 12, 1880, 363, from "hilly shaded forests, western slopes of the Ruahine Range," is separated from D. fibrosa by Colenso by: "rhizome or root-stalk rising only a few inches above ground . . . hairs 2 inches long, shining, chestnut brown, articulated and moniliform their whole length . . . frond obovate or cuneate. profoundly tapering downwards, or somewhat of a rhomboidal figure . . . sori generally form on largest segments, small." The type specimen (W) consists of a portion of rhachis with 7 pinnae. and shows no clear characters separating it from D. fibrosa.

D. microcarpa Col. in T.N.Z.I. 20, 1888, 214, from "forests south of Dannevirke," is described as having "fronds 41/2 feet long including short stipes, 1 foot broad at widest part, sub-membranous-coriaceous . . . sori small . . . inner valve (indusium) scarious." The type specimen (W) consists of a portion of rhachis with 13 pinnae. The pinnae are c. 15 cm. long, finely cut, with secondary pinnae up to 2 cm. long. The pinnules are acute, with lower ones 4-lobed; the sori are c. 0·5 mm. diam. Cheeseman (Man. N.Z. Fl. 1925, 21) states of this and D. sparrmanniana, "both merge gradually into the ordinary form". Miss Crookes (in New Zealand Ferns 1951, 124) says: "D. fibrosa is an extremely variable plant, indeed Colenso split it into three species, but both his forms merge imperceptibly into the normal type." It has not been suggested that the "merging" is due to hybridism.