SOUTH AFRICAN MARINE MOLLUSKS. 101 



ture; inner lip appressed to and reflected over the short base; parietal 

 wall covered by a thin callus. 



Cat. No. 227719, U.S.N.M. (Coll. No. 814), contains three speci- 

 mens from Port Alfred. Two of these are cotypes; one, a young 

 individual of 1 1 postnuclear whorls, has served for our description of 

 the nucleus and the early postnuclear whorls. This measures: 

 Length, 7 mm.; diameter, 2.2 mm. The other, an adult individual 

 having lost the nucleus and probably the first four postnuclear turns, 

 retaining the last 13 whorls, measures: Length, 13 mm.; diameter, 

 3 mm. Cat. No. 227720, U.S.N.M. (Coll. No. 815) two specimens 

 from the same locality. 



TRIPHORIS ELSA, new species. 

 Plate 11, fig. 1. 



Shell elongate-conic, bluish white. Nuclear whorls decollated, 

 the last turn only remaining, which is smooth. Postnuclear whorls 

 moderately rounded, marked by three spiral cords, of which the 

 first is a little anterior to the summit, while the third is as far above 

 the suture as it is separated from the median. The median occupies a 

 position half way between the other two. In addition to these 

 spiral cords, the whorls are marked by slightly protractive, moder- 

 ately strong, rounded axial ribs, of which 18 occur upon all but the 

 last two whorls, which have 20. The junction of the axial ribs and 

 the spiral cords form rounded nodules, which have the long axis 

 parallel to the spiral sculpture. These nodules are well rounded on 

 the posterior cord, while on the median cord they are truncated 

 anteriorly and posteriorly, a little more abruptly anteriorly than 

 posteriorly. On the third cord they are truncated posteriorly and 

 sloped gently anteriorly. The spaces inclosed between the cords 

 form shallow, rectangular pits. The summit of the whorls falls a 

 little anterior to the peripheral cord and allows this to be apparent 

 in all the sutures. Periphery of the last whorl marked by a strong 

 cord, which is separated from the first supra-peripheral cord by a 

 sulcus as wide as that which separates those from the median cord. 

 This sulcus, like the other, is crossed by continuations of the axial 

 ribs, which terminate at the posterior edge of the peripheral cord. 

 Base concave, marked by a slender, spiral cord immediately adja- 

 cent to the peripheral cord. In addition to the above sculpture the 

 entire surface of the shell is marked by fine lines of growth and 

 microscopic spiral striations. Aperture channeled anteriorly; outer 

 lip thin, showing the external sculpture within and rendered sinuous 

 by the external sculpture at the edge; columella stout, curved, 

 covered by a thin callus, which extends over the parietal wall. 



Cat. No. 249678, U.S.N.M., contains two adolescent shells of this 

 species, one of which is the type. They are from Port Alfred (Coll. 

 80737°— Bull. 91—15 8 



