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Show 1892.] LAND-SHELLS OF ST. HELENA. 265 BULIMUS (PACHYOTUS). 14. BULIMUS AURIS-VULPINA (Chemnitz). (Plate XXII. figs. 11-11 d.) Hab. All along Sugarloaf Ridge (Turton). Extinct. With regard to this, the largest extinct snail of St. Helena, Mr. Wollaston admits the resemblance " to a certain extent " to certain Brazilian species, at the same time observing "that much the same type of form exists equally in the Solomon Islands and New Zealand." Whilst agreeing with those remarks, I would point out that although in the Pacific shells referred to the apertures are somewhat similar, the general form, especially of the body-whorl, is much more elongate. On the contrary, B. melanostoma and B. bilabiatus from Brazil, cited by Forbes in comparison, exhibit not only like proportions, but also similar oral characters. Captain Turton in his notes remarks : " The shape appears to me to vary immensely, and therefore I have sent as many as 30 specimens, so as to show all the intermediate forms. The very slender ones are, I suppose, B. darwinianus, but I can scarcely draw any line between them. I noticed that the different varieties of this shell generally (always, I think) came from different parts of the ridge ; and you will observe that the more recent shells which retain their colour do not grow to the same size as the more fossilized ones." I fully concur in the opinion arrived at by Captain Turton respecting B. darwinianus (Plate XXII. fig. 11 d) being merely an elongate form of the B. auris-vulpina. His other observation, with regard to the smaller size of the more recent specimens, is also very interesting. This diminution might be accounted for by the vegetation being less luxuriant and other conditions being less favourable to finer growth than in former times, before the partial destruction of the primaeval forests which then clothed the island. The freshest examples are of a light reddish colour and generally of a somewhat darker tint towards the apex. The top of the plications at the suture are whitish, and there is more or less of this colour variously distributed over the surface in the form of irregular streaks and blotches. A few subfossil snails' eggs obtained at Sugarloaf Ridge along with this species evidently from their size belong to it. They are roundly ovate, being 6| millim. in length and 6 broad. Some other much smaller eggs were also found by Captain Turton at the same place, but in this instance it would be mere guesswork to suggest to which species they belong. (BULIMULUS.) 15. B U L I M U L U S B L O F E L D I , Forbes. (Plate XXII. fig. 12.) Hab. Side Path ; very common (Turton). This species is very like the following in form, but has not the same strong spiral sculpture. However in the best preserved example indications of transverse striae and some oblique faint reddish markings are observable. |