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Show 1S90.] MARINE MOLLUSCA OF ST. HELENA. 2/3 SCALARIA CONFUSA. V Scalaria turricula, Sowerby, partim, Thes. Conch, vol. i. p. 92. Hab. Catanuan, Tsle of Luzon, Philippines (Cuming); Sandwich Islands (Mus. Cuming); N.W. Australia (Capt. Beckett in Brit. Mus.). V * Sowerby seems to me to have included two species under the name S. turricula--the one a distinctly striated shell with unequal varices; the other, which I now name S. confusa, being smooth and with more regular riblets. The true turricula is represented by figure 88 * in the 'Thesaurus,' where the thick varix on the penultimate whorl shows the spine or tooth-like projection at the upper end, a feature not occurring in Sc. confusa. It is only the thick riblets (former peristomes) which have the spine. 'Thesaurus,' fig. 61, fairly represents the form of the present species, but the colour is too red, the varices not fine enough, and the interstices should be smooth and not spirally striated. Fig. 59 in the ' Conch. Icon.' also gives a coarse idea of this species. The St. Helena specimens have the lower half of the whorls light brown, and the upper half dirty white, with oblique faint brown blotches, and all the riblets are white throughout. In comparison with the three specimens from N.W. Australia, those from St. Helena are a trifle more suddenly tapering ; but as both exhibit the same glossy surface similar colour, and varices, I feel convinced that they should be considered as belonging to one and the same species. SCALARIA FRAGILIS, Hanley. Scalaria fragilis, Hanley, Conchologist's Book of Species, p. 63 (1842); Sowerby, Thesaurus, vol. i. p. 88, pi. xxxiii. figs. 64-66 (1844); id. Conch. Icon. pi. v. fig. 29. Scalaria albida, d'Orbigny, Sagra's Hist. Cuba, Moll. vol. ii. p. 17, pi. x. figs. 24, 25. Hab. St. Vincent's and Cuba. Of the five St. Helena specimens, three are rather less slender than the majority of West-Indian examples, but the two others have quite the same form. Species oi Scalaria appear to vary in respect of proportional dimensions. The figure in Hanley's work is not good, but I nevertheless believe that it represents the same species as that described by Sowerby. The latter is, however, certainly identical with -S. albida of d'Orbigny, proved by a comparison of the types. SCALARIA MELLISSI. (Plate XXIII. fig. 13.) Testa Sc. trevelyanae similis, sed paulo robustior, lamellisque longitudinalibus simplicibus, superne haud subspinosis. Longit. 14 millim., diam. 4^. The shells here described were collected by Mr. Melliss, and appear in his list under the name of S. modesta oi C. B. Adams. 1 I retain this as the type because in both of his diagnoses the author refers to the minute spiral striation. |
