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Show 1901.] MOTHER-OF-PEARL OYSTERS. 379 land, usually with a golden margin; while the three Malayan varieties " Manilla " (Sulu Seas and Philippines), " Mergui," and "' Macassar" are usually coloured deep yellow-ochre or brown, with a broad golden border to the nacre, and abundance of " fire," i. e. many-coloured iridescence. Geographical Distribution. All along N. coast of Australia ; E. coast as far south as Townsville (but not in quantities any where south of Cooktown) ; W . coast as far as 20° south in payable quantities, and sparingly as far south as 25° (for above details as to southern limits I am indebted to Mr. E. Munro of Thursday Island). In suitable localities off the coasts of N e w Guinea and the surrounding islands, the D'Entrecasteaux, the Louisiades, N e w Britain, and the Solomon Islands. It is found in many localities throughout the Malay Archipelago; the Aru Islands, coasts of Borneo, Sulu Seas, Philippines, Macassar, Mergui, &c. In the Indian Ocean proper it is unknown, and I cannot find any authentic record of its range extending far into the Pacific. [My friend Mr. S. Pace has drawn m y attention to the presence of hinge-teeth as an occasional character in the young of this species. A slight thickening of the hinge posterior to the ligament, in grown examples, may well be a trace of the obliterated lateral.] DIVISION 2. Hinge with one or two minute tubercular teeth anterior to ligament; and a small elongated lateral tooth, running from the hinge, posterior to ligament, for a short distance on the surface of the nacre. Section a. Shell massive, contorted, irregular in outline. Anterior margin with a very broad notch, ventral to rostrum ; posterior margin entire or slightly sinuate, posterior process of hinge absent. Teeth feebly represented in the young shell, lost with age. Species 3. MARGARITIFERA CAPENSIS. Avicula (Meleagrina) margaritifera, L., var., Dunker, 1872, p. 58, tab. 20. figs. 1 & 2; Algoa Bay. Avicula (Meleagrina) capensis, Sowerby, 1889, p. 158, pi. in. fig. 10 ; S. Africa. Specimens in the British Museum from Bazaruto Isl., E. Africa (J H Ponsonby, Escp), and Port Elizabeth (J. H. Ponsonby, Esq.). I can find no evidence of this species having ever found its way into the London Mother-of-Pearl markets. The thick massive shell should be of service for the manufacture of some of the articles for which M. maxima is used, but the dull, somewhat porcellaneous lustre of the nacre would naturally detract greatly from its value. |