Art. XXII.—Description of a New Species of Pimelea.
[Read before the Nelson Philosophical Society, 11th December, 1893.]
Pimelea suteri, n.s.
Stems suberect or spreading 4in.—10in. high, much branched, branches slender, naked and scarred below, bark black; sparingly silky above with rather long straight hairs. Leaves about ⅜in. long, erecto-patent, sessile, narrow linear-lanceolate, more or less concave above, with ciliated margins and apices, scarcely acute. Flowers small, in 5–8 flowered capitula rarely exceeding the leaves; perianth silky or villous. Fruit baccate, ovate-acuminate, hairy at the apex, opaque, red.
Hab. South Island: Dun Mountain, Nelson, alt. 3,000ft. P. Lawson! (1868). W. T. L. Travers! R. I. Kingsley!
This species is most nearly related to P. prostrata, Vahl., and P. urvilleana, A. Rich.; but the fruit is quite unlike that of any other species. Mr. N. E. Brown, of the Kew Herbarium, who has kindly compared my plant with type specimens of various species, informs me that he considers it specifically distinct, although it is identical with P. prostrata, var. γ, of the “Handbook of the New Zealand Flora.” It differs, however, from that form in the leaves never being ovate, truly acute, or glabrous: in all the specimens examined the hairs are confined to the margins and spices of the leaves.
As in all the New Zealand species with small leaves, the flowers of P. suteri are functionally diœcious, although apparently hermaphrodite. The staminate flowers may be distinguished at a glance by the greater length of the perianth; the erect anthers are distinctly exserted and produce abundance of pollen, while the short style, with its small abortive stigma, is invariably glabrous.
In the pistillate plant the anthers are invariably abortive, and are hidden in the tube of the perianth; the large capitate stigma, thickly clothed with short papillose hairs, is prominent at the mouth of the tube, where it takes the place of the anthers in the proper staminate plant.
My specimens do not show any instance in which the style in the proper staminate plant is bent on one side and protruded beyond the anthers, as is the case in the large-flowered forms of P. prostrata.
The remarkable dimorphism of the flowers in this genus has long been observed, but is not yet fully understood; it is occasionally correlated with slight differences in the habit and leaves of the plant, so that the different sexes in certain localities may be distinguished at sight over large areas. This was first observed at Great Omaha in 1864, when I forwarded specimens of P. arenaria showing this feature to Sir Joseph Hooker, who was greatly interested in the phenomenon, although unable to account for it at that time. In many localities, however, there is no obvious difference between the staminate and pistillate flowers except the smaller size of the latter; and at present it is not proved that the occasional difference in habit and foliage is permanent, although its occurrence over large areas is certainly striking. I have never met with true hermaphrodite specimens; in all forms with perfect anthers the stigma is invariably glabrous and abortive so far as my observations extend, but it must be admitted that wider observation is necessary.
It affords me great pleasure to connect the name of the Right Rev. Dr. Super with this species, and to acknowledge the help he has frequently rendered in forwarding specimens of various New Zealand plants.