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Show 1892.] LAND-SHELLS OF ST. H E L E N A . 269 Hab. Sugarloaf Quarry (Turton). Extinct. This is a very minute species, with very oblique, slender, and somewhat remote costulse and no teeth within the aperture. 25. SUCCINEA SANCT^E-HELEN^E (LeSSOn). Hab. High ground among native vegetation (Turton). Living. 26. SUCCINEA PICTA, Pfeiffer. Hab. All over Sugarloaf Ridge, common (Turton). Living. 27. SUCCINEA BENSONIANA, Forbes. Hab. Long Range, Sugarloaf Ridge, common, both living and extinct (Turton). Little can be suggested with regard to the origin or relationship of the above three species, for, as is well known, Succineas all the world over have a remarkably strong family likeness. That they are not importations of modern times, however, is proved by the fact that one of them occurs in a semifossil condition along with other extinct forms of land-shells. B. Introduced Species. Through the kindness of Mr. E. L. Layard I have had the opportunity of examining the types of two of Benson's species, namely:-Achatina veru and Bulimus compressilabris. The former I regard as identical with the West-Indian Ccecilioides gundlachi (Pfeiffer), which is synoymous with Macrospira aperta of Guilding from St. Vincent's, specimens of which, from Guilding's collection, are now in the British Museum. As it was found in the Public Gardens at Jamestown there is every probability of its being a comparatively recent introduction along with West-Indian plants. The Bulimus compressilabris also appears to be an introduction from the West Indies, for it is identical with the Stenogyra ascendens of Poey from Cuba, which I believe to be merely a slender form of St. goodallii, Miller. The remaining introduced species have been enumerated in the early part of this paper. EXPLANATION OF THE PLATES. PLATE XXI. Figs. 1, la. Patida spurca, p. 260. 2-2 b. diancs, p. 261. 3-36. persoluta, sp. n., p. 261. 4-4 b. Icetissima, sp. n., p. 261. 5. bilamellata, p. 262. 6-6 b. vernoni, sp. n., p. 262. 7-7 b. pseustes, sp. n., p. 262. 8-8 c. polyodon, p. 263. 9-9 c. minutissima, sp. n., p. 264. 10-10 c. leptalea, sp. n., p. 264. PROC. ZOOL. Soc-1892 No. XIX. 19 |
