Art. XXII.—Description of two little-known Species of New Zealand Shells.
[Read before the Hawke's Bay Philosophical Institute, 14th November, 1881.]
Although just forty years have passed since I first detected and made known these two shells, one marine and one fresh-water, which I now bring before you, I have good reasons for believing they are still but little known. Their scientific description, etc., was early published in the “Tasmanian Journal of Natural Science,”* but I do not find them noticed in any of the modern conchological works in our library, under my own or any other specific names; neither are they included in the exhaustive “List of New Zealand Mollusca,” recently laboriously compiled from almost all conchological authorities by Professor Hutton, and published last year by the New Zealand Government. I therefore conclude that they are still but little known. This, however, may be easily accounted for, if, as I suppose, the single localities in which I separately found them are their only known habitats; as such are quite out of the way of both the scientific and general traveller; and although I sought them diligently in my early and general collecting of the shells of this country, I never met with these species anywhere else. At the time, however, of their discovery, I distributed several specimens to various parts of the world.
You will not fail to note, in examining the specimens before you, how exceedingly well they have kept both their original colours and freshness of epidermis, more resembling specimens newly obtained, than those of forty years slumbering in a cabinet. In again giving their scientific description, I shall, on account of conformity, confine myself to the terms I used in the original drawing up, although at that very early period without scientific books.
Patella solandri: Shell oval, anteriorly truncated, much depressed, faintly striated longitudinally, diaphanous, fragile, covered with a thin epidermis; inside, smooth, glossy; vertex, very much anteriorly inclined, sub-acute, produced, slightly recurved; margin, entire, obsoletely crenulated within; colour, bluish green, concentrically streaked with brown, beautifully blotched, or tortuously undulated, with same colour towards margin; 5–7 lines long, 4–5 lines broad.
Hab. Adhering to the underside of large smooth stones; Tokomaru (Tegadoo) Bay, East Coast, North Island of New Zealand.
[Footnote] * Discovered in December, 1841, and published in “Tasmanian Journal of Natural Science,” vol. ii., pp. 226, 250.
Unio waikarense. Shell, oblong, or oblong-ovate, concentrically and irregularly sulcated, sub-diaphanous, inflated; anterior side produced, obtuse, slightly compressed; posterior slope, keeled, sharp: base, slightly depressed; umbones, decorticated, flattish, much worn; primary tooth, large crested; epidermis, strong, overlapping at margin, wrinkled on anterior slope; colour, brownish-yellow on posterior side, shading into dusky-green on the anterior, with alternate light-coloured lateral stripes; 3½ inches broad, 2¼ inches long.
Hab. Waikare Lake, mountains, interior of the North Island of New Zealand.
The largest and handsomest of all the known New Zealand species of the genus.