Art. XXXV.—Notes on the Occurrence and Habits of some of our New Zealand Plants.
[Read before the Southland Institute, 13th May, 1884.]
Glossostigma elatinoides, Benth
This plant occurs on the flats of the Oreti, in the bottom of ditches that have been opened for some time. Its corolla is pale blue and very pretty; ¼-⅓ inch. The strap-shaped stigma is irritable, and springs back on being touched, leaving the anthers exposed; and taking a place among the petals, looks exactly like an additional one. Before springing back it forms a hood over the anthers, and looks like an Orchid or a Lobelia. This plant has not, so far as I know, been reported from the south before. It does not occur on the flats except where a ditch has been opened, thus leading us to suppose that the subsoil is full of its seed, but that the climate is no longer suitable to its growth, and that it can only grow now under exceptional circumstances of shelter and moisture.
Pteris scaberula, A. Rich
Like the last-mentioned, this plant occurs in Southland under somewhat exceptional conditions. It also springs up where ditches have been opened along the roadsides, in the cemetery, and in sheltered spots on the Bluff Hill.
Its spores are no doubt lying in the gravel-beds of the subsoil, and would thus appear to have been of universal occurrence at some past time. Its local and exceptional occurrence at the present day, would also argue the decrease of the temperature, and hence of the moisture held in solution, a change which is also evidenced by the disappearance of the ordinary bush over wide tracts of country in the South Island.
Corysanthes macrantha, Br
This fine orchid occurs plentifully, but always in one kind of situation, where water is oozing out of a bed of gravel on a slope. It likes a burn-brae, and is there only found on the shady side. It is particularly luxuriant and large in Southland; its leaves as large as a florin, bright green and succulent. It folds its large apron (labellum) so closely around the short style and the pollen masses that it must be a very small insect indeed that is able to find its way to them. It not only seems independent of the services of insects, but takes good care that they do not get at its treasures.
Stylidium subulatum, Hook. f
This curious little plant occurs plentifully over the Seaward Moss, and seems to be more closely allied to the Pratia family than has been generally supposed. The fruit is not one-celled as stated in Hooker's “Handbook,” but is strongly two-celled, the cartilaginous septum being particularly strong and permanent. The seeds are agglomerated on a spot in the middle of the septum on each side of it; and from those in the centre having longer placentas than those around the outside of the bunch, they look like a hemispherical mass, somewhat like the spore-bundles of Polypodium.
Pelargonium australe, Willd., var. prostrata
This variety, hitherto unreported in New Zealand, occurs in the Seaward Moss, and varies in size from 2 to 8 inches or more, with dark brownish-purple foliage and much-branched prostrate almost creeping stem; root-stock fusiform and very short and stout, flowers small, very slightly irregular and pure white, pink when dry.
Callitriche verna, Linn
It does not seem to have been observed that the first flowers of spring of this species are all male, with very long filaments. After a few days the male flowers decrease, and a few female flowers begin to appear on the same plants, and sometimes on the same peduncle with the male. Later on the flowers are all female, and one may search in vain for a single male flower, and yet the fertilization goes on, no doubt from the pollen grains adhering to the moist foliage and remaining in a fit state for germination during the summer; this is also observable in the Gunnera family, all the New Zealand species of which seem to be more or less polygamous. But it is observable that the first flower-scapes that are sent up in spring bear only
male flowers, and after the pollen which is green has been shed, they wither rapidly away. A few days later, and the scapes coming up have often both kinds of flowers mixed, which gives the fruit-spike when ripe a ragged or interrupted appearance very common in some species, from the places of the male flowers remaining vacant. Later still the scapes (which come up in succession all the summer) have nothing but female flowers, and these have the finest fruit. The scapes which bear both kinds of flowers are generally barren, unless the female flowers predominate, in which case a few drupes come to maturity, but are shy, small and half-withered looking.
The male scapes attain their full length before flowering, which they do in a few days; the female lengthen after flowering, and indeed till the fruit is mature. The female flowers are developed as soon as the scape appears in the axil of the leaves, and are in full flower at, or even under, the surface, the long hairy or papillose styles spreading like rootlets among the débris of withered leaves, as if in search of the pollen grains which had been shed in spring, and are probably still remaining in a fertile condition among the moist foliage.
Gunnera hamiltonii, Kirk, n. sp
Mr. Kirk has not yet sent me the description of this handsome and unique species. It is extremely local, occurring in patches on the hills near the New River Heads. It completely excludes every other kind of vegetation, and from its graceful cuneate-deltoid deeply and sharply dentate foliage gives the surface a peculiarly crisp appearance. The extremely coriaceous strongly-ribbed leaves tufted densely together support the foot, and spreading from a hollow centre give the ground a bird-nested appearance. The succulent leaves are extremely rich in lime and silica and give off, when old, the epidermis as a grey paper. The flowers of this species are spiked, the anthers sessile on very stout scapes, not crowded; the drupes on still stouter peduncles, as thick as a goose-quill and two to four inches long, bright red, and with the drupes almost sunk in the fleshy peduncle, not crowded, but occupying an inch or more of the top of the scape.
Tillæa hamiltonii, Kirk, n. sp
This Tillæa, occurring on the flats of the Makarewa, also takes to the river-bed, and, along with other species of aquatic or, rather, semi-amphibious plants, carpets the river-bottom to a very considerable depth. This is a remarkable feature of the Makarewa, and, whatever be its cause, is a very strange peculiarity.
Lindsæa linearis, Swartz
This fern occurs plentifully in the Seaward Moss, but still in a very local way. It occurs in strips across the plains, as if following the outcrop of
some particular gravel bed or some condition of soil or moisture. In some places it is restricted to a strip a few yards wide, but extending lengthwise, following the same level round the little elevations of the plain. It grows in some places very luxuriantly; fronds 6–8 inches high.
L. trichomanoides occurs in the Longwood Ranges, but is very rare. I have only seen one specimen–-brought in by a surveyor, who took it for a maiden-hair fern.
A Geranium with pure azure blue flowers occurs on the hill of the New River Heads. I cannot distinguish this species in other respects from G. molle, Linn., except that it has much heavier foliage. I have sent specimens to Mr. Kirk, but have not yet received his reply.