. Bulletin of the British Museum (Natural History). 195c 195b. 197b 197a I Figs 195-197 Vitrinella (Vitrinellops) hauxwelli sp. nov. Pebasian; Pichana, Peru; Hauxwell Colin. 195, holotype, GG19952; a, dorsal view; b, front; c, ventral view; all X 50. 196, paratype, GG19954; front, x 50. 197, paratype, GG19953; a, slightly oblique side view, x 50; b, view of early whorls, x 120; c, dorsal view of protoconch and first growth lines, x 500. Compare Fig. 193. Name. For L. dc Greve, who described and figured the specimen in 1938. Diagnosis. Comparatively large, involute Vitrinellops with l
. Bulletin of the British Museum (Natural History). 195c 195b. 197b 197a I Figs 195-197 Vitrinella (Vitrinellops) hauxwelli sp. nov. Pebasian; Pichana, Peru; Hauxwell Colin. 195, holotype, GG19952; a, dorsal view; b, front; c, ventral view; all X 50. 196, paratype, GG19954; front, x 50. 197, paratype, GG19953; a, slightly oblique side view, x 50; b, view of early whorls, x 120; c, dorsal view of protoconch and first growth lines, x 500. Compare Fig. 193. Name. For L. dc Greve, who described and figured the specimen in 1938. Diagnosis. Comparatively large, involute Vitrinellops with low spire; adapical surface of whorls weakly convex and sutures only slightly incised; aperture broad; umbilicus narrow. Description. The unique shell is rather involute in both dorsal and ventral views. There are about 3'/> whorls, and in the later growth stages the expansion rate increases slightly. Traces of two rather strong growth halts just prior to the aperture suggest that full size is being reached. The early whorls strongly resemble those of the preceding species in size and shape, but neither growth lines nor a growth halt indicating the transition from embryonic to post-cmbryonic shell are visible at the half-whorl stage. At IV2 whorls, however, some almost orthocline, slightly forwardly-bowcd growth lines can be observed with difficulty, but they arc not clear enough to be identified as representing the embryonic aperture. The upper surface of the shell is slightly domed and the sutures of the weakly convex whorls arc not deeply impressed. The lower surface is considerably more convex and the umbilicus is narrow: although infilled with immovable matrix, it is unlikely that whorls preceding the body whorl would be visible. The aperture is much broader than high and its periphery is rather below half whorl height. The inner lip is almost straight and vertical, but its upper left portion is slightly indented by the previous whorl. The growth lines arc markedly opist
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