OCR Text |
Show 1901.] MOTHER-OF-PEARL OYSTERS. 391 processes of 31. vulgaris. Ground-colour white, with 6 to 10 green, brown, or black radii, which are very variable, in some cases being almost entirely suppressed, in others being confluent, so that the shell is of a uniform dark colour. Interior of the lip white, with black or dark purple blotches, corresponding to the radial bauds. Nacre lustrous, tinted with brassy yellow, with a steely sheen, transparent, showing the blotchy external markings distinctly through its substance, as depicted iu Gould's figure. Length of hinge 28 mm.; total antero-posterior measurement of shell 37 mm., do. of nacre 28 mm., total dors.-ventr. measurement of shell 37 mm., do. nacre only 28 m m . The greatest anteroposterior measurement of shell is in the ventral third. Distribution. Conflict Group, British N e w Guinea, on dead coral-reef flats (H. L. J.). Other localities in N e w Guinea waters : Moresby Island, Samarai, Bonvouloir Group, &c. (H. L. J.); Badu (Mulgrave Island), Torres Straits, in rock-pools (H. L.J.). "Australia"; Keeling Island; Fiji; Lord Howe Island (J. Brazier, Esq.); Samoa (Rev. S. J. Whitmee); Loo Choo Isls. (H. Seebohm, Esq.) : in British Museum. ? Distinct, S. Africa, Ponsonby coll., B.M. Species 27. MARGARITIFERA MAURITII, n. sp. (Text-fig. 95.) Type B.M. No. 1885.9.19.14. Attached to pumice-stone found floating off Mauritius (Robillard). Shell oblique, inequivalve, left valve very convex, right valve comparatively flat. Posterior margin very distinctly sinuated, as in 31. vulgaris. Lappet-like lip-processes resembling those of Text-fig. 95. Margaritifera mauritii, nat. size. M. pitcaimensis, M. lurida, and 31.panasesa>, strong and finger-like, without transverse markings. Teeth as in 31. vulgaris. Coloration unusually rich compared with the rather washy external markings of most species ; very variable, from dark reddish brown to golden yellow and pale grey, with six to eight white or dark radii of J 26* |