. Mollusca ... Mollusks. PLEOTOPYLIS. 145 chestnub above and at the sides. The specimen figured was received by me as Plectopylis pachystoma, Theobald ; but as I am not aware that this name was ever published I consider it expedient to discard the name altogether. A specimen in the collection of the. 6 c Kg. 76.—Plectopylis bensoni, var. venusta. late Dr. von Miillendorff, likewise labelled P. pachystoma, I am unable to separate from the present variety, although it shows no flaramulation and the peristome is white; in other respects it is identical. Var. breviplica, Gude. Plectopylis achatina
. Mollusca ... Mollusks. PLEOTOPYLIS. 145 chestnub above and at the sides. The specimen figured was received by me as Plectopylis pachystoma, Theobald ; but as I am not aware that this name was ever published I consider it expedient to discard the name altogether. A specimen in the collection of the. 6 c Kg. 76.—Plectopylis bensoni, var. venusta. late Dr. von Miillendorff, likewise labelled P. pachystoma, I am unable to separate from the present variety, although it shows no flaramulation and the peristome is white; in other respects it is identical. Var. breviplica, Gude. Plectopylis achatina, var. breviplica, Gude, Science Gossip, n. s v 1898, p. 134, fig. 87. Differs from the type and all the other known varieties by the much more shallow umbilicus. It resembles the variety infra- fasciata in outline, but it is of a uniform dark brown, with a somewhat polished surface, and the last whorl widens more suddenly at the aperture. The basal horizontal parietal fold is very short, not extending on either side beyond the two lower arms of the main median fold ; the first palatal horizontal fold is considerably more elevated than in the other forms, and is bilobed j the second and third horizontal folds are also more elevated, the latter fold has a short fold above its posterior portion; the vertical lamina is also more elevated, and in place of the usual denticle posteriorly to its lower extremity is an elevated ridge, quite united to the plate. Major diam. 19, minor 16 mm.; alt. 7 mm. Hab. Burma. Plectopylis bensoni, var. breviplica has a much shallower umbilicus, and is thinner and more fragile than any other form of P. bensoni known to me. It is somewhat like the variety infrafasciata, but it is devoid of the white band on the lower side; the last wborl also widens a little more than in that variety, but is less deflected, and the aperture is more sloping from top to base ; there are also important differences in the armature, the lower horizontal parietal fold bein
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Keywords: ., bookauthorg, bookcentury1900, bookdecade1900, booksubjectmollusks
