236 PROCEEDI-SGS OF THE NATIONAL MUSEUM. vol.46. 



ished; aperture ovate, peristome entire, not interrupted by the body; 

 a minute chink behind the pillar lip but no umbilical perforation. 

 Length, 2; diameter, 1 mm. 



Station 6040, near Alexandria, Louisiana. Type, U. S. Nat. Mus., 

 No. 166309. 



This little shell indicates by its color that when living it was of a 

 dark, perhaps purplish, color. 



PYRGULOPSIS? SATILLA, new species. 



Plate 22, fig. 3. 



Shell minute, smooth, with a rather swollen nucleus of a whorl and 

 a haK, and three or more subsequent sharply carinated whorls; the 

 carina is at the anterior third of the whorl which slopes flatly down to 

 it from the preceding suture; there is a second carina in front of the 

 first on which the suture is wound and which is only visible on the 

 base of the last whorl which is flattish. Aperture defective in the 

 specimen. Length, 1.2; diameter, 0.5 mm. 



Station 6040, near Alexandria, Louisiana. Type, U. S. Nat. Mus., 

 No. 166310. 



I refer this extremely minute shell to Pyrgulopsis at a venture, as 

 it can not be regarded as a Paludestrina or the tip of a Turritella. 



NERITINA SPARSILINEATA Dall. 



Neritina, sp. indet. Aldrich, Nautilus, vol. 24, pt. 11, p. 131, No. 7, 1911; vol. 26, 

 pi. 1, figs. 3, 4, 1912. 



Stations 3614, 6040, 6132, 6440, and 6445. 



This species was figured but not named by Messrs. Aldrich and 

 Pilsbry, and though the attention of Doctor Pilsbry was called to the 

 omission, no name has yet been printed as far as I know. It is one 

 of the most widespread and characteristic species of this horizon. 

 An adult specimen measures 10 mm. in height and 7.5 mm. in greatest 

 diameter. It is remarkable for its subacute conical form. The black 

 lines vary as in N. pupa. The labial callus is profuse and the inner 

 lip obsoletely striated or smooth. 



PLANORBIS OPHIS, new species. 



Plate 21, figs. 3, 4. 



Shell small, deeply and closely enrolled, the summit slightly less 

 so than the base, and showing about foiir whorls; the coil from in 

 front appears almost exactly symmetrical; aperture semilunate, the 

 body protruding well into it, outer lip (adult?) thin, sharp; surface 

 pohshed almost smooth above, the striations in harmony with the 

 incremental fines are more perceptible on the base; the surface of the 

 spire is concavely flattened, but as usual the basal parts in the umbil- 

 ical cavity retain their rotundity. Diameter of coil 4; height of 

 aperture 2.6 mm. 



