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Show 280 MR. E. A. SMITH ON SHELLS FROM [Feb. 15, The two specimens of this species are apparently both young, as the characteristic deviating body-whorl is not yet developed. 1 he base is widely umbilicated, as in the Brazilian S. Candida. When adult this must be the giant of the genus, and a most remarkable shell. The costulae are strong, remarkably flexuous beneath the suture, and then obliquely arcuate across the whorls ; what I have described as striae upon the left side of them, or that last formed and nearest the aperture, is rather a kind of pitting. 7. STREPTAXIS CRAVENI. (Plate XXXII. figs. 5, 5 a.) Strepaxis craveni, E. A. Smith, Annals, I.e. Shell narrowly umbilicated, obliquely distorted, smooth, glossy, dirty milky-whitish. Whorls 7, slightly convex, closely costulately striated beneath the suture. Last whorl suddenly descending in front, then rising somewhat upon the preceding whorl, very obliquely deviating. Aperture oblique, edentulate ; outer lip (viewed laterally) sinuated at the suture, then prominently arcuate and oblique beneath, a little thickened and reflexed. Columella and basal margin thickened and narrowly reflexed, the former a trifle arcuated. Length from apex to base of aperture 29 millims. ; diameter of last whorl 22 ; aperture 15 high, 12| broad. Hab. On hills between the mouth of the river Dana and M o m basa, East Africa (Kirk). This is one of the finest species of Streptaxis yet discovered, and remarkable on account of the peculiar outline of the labrum, the smoothness and polish of its surface, and its large size. I have much pleasure in naming it after m y friend Al r. A. E. Craven, who has contributed to our knowledge of the shells of the East-African region, and has also written a very important monograph of the microscopic genus Sinusigera, and other valuable contributions to conchological science. 8. STREPTAXIS MOZAMBICENSIS. (Plate XXXII. figs. 6, 6 a.) Streptaxis mozambicensis, E. A. Smith, Annals, I. c. Shell small, linearly rimate, whitish, smooth, glossy. Whorls 6, convex, crenulated beneath the deep suture ; last whorl oblique, of the same width as the preceding, descending in front, and briefly ascending at the aperture, a trifle flattened above the aperture ; the latter circularly lunate, small, edentulate ; outer lip a trifle arcuate viewed laterally, oblique, narrowly expanded. Columellar margin more broadly reflexed. Height 7g millims., diameter of last whorl A\ ; aperture 3 long, 2\ wide. Llab. Between Lake Nyassa and the east coast (Thomson). This species is smaller and less distorted than S. JcirJci, Dohrn, and has merely a linear umbilical fissure. It is likewise smaller than S. enneoides, Martens, not perforate, smooth, and has more convex whorls. |