172 BULLETIN 91, UNITED STATES NATIONAL MUSEUM. 



DISCOPSIS ALFREDENSIS, new species. 

 Plate 31, figa. 1, 2, 3. 



Shell small, sublenticular, white, excepting the nuclear whorls, 

 which are pale chestnut brown. Nuclear whorls two, small, well- 

 rounded, forming an elevated helicoid spire with strongly impressed 

 suture. Postnuclear whorls very wide, moderately rounded, marked 

 by decidedly retractive, wavy riblets, which, on the last half of the 

 last volution, become irregular and strongly wavy. These riblets 

 are about one-fourth as wide as the shallow concave spaces that 

 separate them. The latter are crossed by spiral threads which are 

 almost equal to the axial riblets in strength. There are about 20 

 of these between the summit and the periphery on the last turn. 

 On the last half of the last turn these also become decidedly irregular 

 and wavy, and the entire sculpture of this portion of the shell assumes 

 a crinkly appearance. Periphery strongly angulated. Base with 

 a very broad funnel-shaped umbilicus, which occupies fully half the 

 space, and which is bordered by a tumid area at its exterior limit; 

 the space between this tumid area and the peripheral angle is slightly 

 concave. The entire surface of the base is marked by the contin- 

 uation of the axial riblets, which are somewhat sinuous and become 

 closer approximated here than on the spire. These riblets extend 

 strongly into the umbilicus. The spaces between the riblets are 

 marked by fine spiral striations. Aperture very large, very oblique, 

 the basal and outer lip forming a decided angle at the periphery; 

 posterior angle obtuse; outer Up decidedly patulous, thin, showing 

 the external sculpture within; inner lip curved, thin, slightly reflected, 

 the outer and the inner lip almost approaching each other on the 

 parietal wall. 



The type and another specimen of this species, Cat. No. 250533, 

 U.S.N.M., come from Port Alfred (Coll. No. 1406). The type has 1.1 

 postnuclear whorls, and measures: Greater diameter, 1.8 mm. 



DISCOPSIS AFRICANA, new species. 

 Plate 33, figs. 5, 6, 7. 



Shell small, discoid, bluish white. Nuclear whorls two, well 

 rounded, smooth, forming a depressed helicoid spire with strongly 

 impressed sutures. Postnuclear whorls one and one-fifth, expand- 

 ing rapidly in size, marked with a strong, lamellar, wavy, peripheral 

 keel, which has a ruffle-like appearance. The space between the 

 summit and this keel is marked with spiral cords, of which 17 are 

 apparent on the outside of the outer lip. Of these, the fourth below 

 the summit forms a strong shoulder, the fourth, sixth, ninth, eleventh, 

 thirteenth, and fifteenth being stronger than the rest, while the 

 remainder are of about equal strength. The space between the one 



