Art. LXIII.—Notice of the Discovery of Monoclea forsteri, Hook., in New Zealand.
[Read before the Wellington Philosophical Society, 2nd February, 1878.]
In “Flora Novæ-Zelandiæ” and “The Handbook of the New Zealand Flora,” a plant of general distribution in this country is doubtfully described, in the absence of fruit, as Dumortiera hirsuta, Nees, the specimens apparently differing from that plant only in their larger size. Fruiting specimens recently obtained near Wellington show that it is the long-lost Monoclea forsteri, Hook.* (Anthoceros univalvis, G.E. Forst., MS.), all our knowledge of which was obtained from Forster's original specimens, and we were even destitute of exact information as to the locality in which it was collected.
Monoclea is a monotypic genus, and with Calobryum forms a section of Hepaticœ characterized by the solitary unilocular sporangium destitute of a columella, and having the elaters carried away with the spores.
[Footnote] * Musci Exotici, II., p. 174.
The thick, fleshy, irregularly-lobed and imbricated fronds of this common plant are so well known to every New Zealand botanist as to need no description. Fructification springing from cavities in the substance of the frond, tumid on the under surface, and opening by slits on the upper surface near the margin. Peduncles 1–3 in each cavity, 1–1.½ inch long, succulent, white or yellowish, the base of each surrounded by a delicate, stipitate, tubular perianth ⅔–½ inch long, with a two-lobed mouth, the lobes jagged or rarely lacerate, not extending beyond the cavity. Peduncle consisting of two separate tubes closely fitting one within the other. Capsule oblong-cylindrical, coriaceous, faintly striated, sub-erect or inclined, dehiscing longitudinally, at length expanding into an oblong flattened valve coarsely striated within. Columella 0. Elaters and spores forming a densely matted dark-brown mass; elaters vermiform, with intersecting spiral bands; spores globose, minutely punctate.
The capsule is at first erect, but becomes inclined or even horizontal in dehiscence.
Our plant is frequently found growing in situations where it must be submerged for the greater part of the year; in places of this kind its fronds are perfectly flat and less coriaceous than in the usual state.
The fruiting condition appears to be remarkably local; my specimens were obtained from the head of a gully running into the Kaiwarawara. Mr. Buchanan has collected fruiting specimens at Wainuiomata; these are the only instances of its being found in fruit, since its discovery, most probably in the South Island, by Forster more than a century ago. It appears to fruit only during the spring months, October and November.