Art. LVIII.—On Lindsaya viridis, Colenso.
[Read before the Otago Institute, 17th January, 1878.]
This elegant fern was originally discovered at Mangarewa, in 1842, by Mr. Colenso, and described by him as Lindsœ viridis three years later, but owing to its having been referred to L. trichomanoides by Sir W. J. Hooker, in 1846, it is only after the lapse of thirty years that its specific validity has become recognized in Europe, although it is separated from its nearest allies by strongly marked differential characters. Without doubt this long neglect is in part owing to the rarity of the plant itself, for, although occurring in both islands, it is remarkably local, and for the most part its habitats are far apart. The few New Zealand botanists who have collected it are unanimous in their opinion as to its specific validity.
In the first edition of “Synopsis Filicum,” published in 1868, Mr. Baker separated our plant from L. trichomanoides and united it with the Australian L. microphylla, Swartz, but two years ago was led to reconsider the question through Wanganui specimens transmitted to Kew by Mr. H. C. Field, under the idea that it was still considered a form of L. trichomanoides. Mr. Baker adopted the view held by botanists in the colony and published our plant as
a distinct species, under its original name, evidently without being aware that it was described by Mr. Colenso thirty years ago. I have, therefore, the greater pleasure in appending a description of the species, for the use of local botanists, that it affords me the opportunity of presenting the claims of its discoverer in their proper light.
Colenso, Filices Novæ Novæ Zelandiæ, p. 14 (1845); Tasmanian Journal, II., p. 174.
Lindsaya viridis, Colenso.
J. G. Baker in Journal of Botany (new series), IV., p. 108.
Lindsœ trichomanoides, Dryander (in part).
Hook., Species Filicum, I., p. 218; Hook. fil., Fl. Nov. Zel., II., p. 20: Handbook N.Z. Flora, p. 359.
Lindsaya microphylla, Swartz (in part).
J. G. Baker in Synopsis Filicum, edits. 1 and 2, p. 110.
Fronds tufted, 6–12 inches long, 1 inch wide, membranous, bright green, stipes 1–3 inches, triquetrous, channelled, shining, naked except a tuft of linear brown scales at the base, frond lanceolate, or lanceolate acuminate, bi- or tri-pinnate, rachis flexuous; pinnæ ascending, alternate, 1–1 ½ inch long, obliquely lanceolate, or rhomboid lanceolate; pinnules simple or deeply lobed, or cut to the base into 2–4 linear cuneate segments, margins truncate, erose, about a line deep and twice as broad; veins indistinct, simple or rarely branched.
Hab. On wet rocks.
North Island: Port Fitzroy, Great Barrier Island, plentiful about waterfalls—Mr. Springall! Manukau Harbour, dripping rocks at the Huia Creek, and waterfalls between the Huia and the sea—T.K. Te Whau—T.K. Mangarewa—Mr. Colenso. Wanganui River—H. C. Field!
South Island: Nelson, under high rocks in a deep ravine, Massacre Bay—Lyall. Canterbury—Sinclair and Haast. Hokitika—W. H. Tipler! West coast of Otago—J. Buchanan.
The Nelson and Canterbury habitats are stated by Mr. Baker in the “Journal of Botany,” on the authority of specimens in the Kew herbarium. I have reason to believe that the supposed Canterbury specimens were collected by Dr. Sinclair at the Huia, and accidentally misplaced, so that the habitat in question requires confirmation.
Our plant attains its greatest luxuriance on vertical dripping rocks where the fronds grow at a right angle to the face of the rock, and are narrower and more rigid than when growing on a horizontal surface. In the latter situation the fronds are radiating and drooping at the tips, with the pinnæ somewhat spreading, so that the frond is relatively wider. The finest
specimens I have seen were growing on vertical dripping rocks at the Huia Creek; some of the fronds are fully sixteen inches long, but not quite so wide as shorter fronds of more lax habit grown on a horizontal surface at Port Fitzroy. In some places where it has the advantage of a continuous supply of moisture, it is exposed to the glare of the sun for a portion of the day, but with little appreciable effect on its delicate texture.
In an immature state this species may easily be mistaken for a Davallia from its narrow sori, which are never wider than twice their depth, and do not extend to the lateral margins of the segments. Mr. Baker points out that “the anterior valve is a continuation of the lamina, while the posterior valve is membranous, both alike incised.”
The affinities of Lindsaya viridis are with L. trichomanoides, Dryand., and L. microphylla, Swartz. The former differs from our plant in its creeping, chaffy rhizomes, broadly ovate coriaceous fronds, spreading, usually opposite pinnæ, and fan-shaped segments with branched veins; it is confined to forests, and extends from the North Cape to Dusky Bay. L. microphylla is confined to temperate Australia, and is distinguished from L. viridis by its larger size, more distant pinnæ, and the sori forming a continuous marginal line, the width being more than twice the depth. L. viridis is endemic in New Zealand. L. trichomanoides is found also in Tasmania, New South Wales, and Fiji.