124 PROCKEDINGS OF THE NATIONAL MUSEUM vol.70 



suture distinct, not deep; surface smooth except for faint incremental 

 lines, and on the base two strong widely spaced threads around 

 the umbilical pit and a few faint spiral striae behind them; base 

 rounded, umbilicus minutely perforate; aperture rounded with a 

 small angulation above, the peristome continuous over the body, thin, 

 and not reflected. Height, 3 mm.; diameter, 4 mm. U. S. Nat. 

 Mus. Cat. No. 108146. 



Two specimens off Fernandina. 



This differs from typical Lydiplmis in being less depressed and 

 without carinae, but seems most nearly allied to that genus. 



LYDIPHNIS TRILIX Bash 



Skenea trilix Bush, Comm. Fisheries Rept. for 1883, p. 684, 1885. 

 Circulus trilix Bush, Trans. Conn. Acad. Sci., vol. 10, p 127, pi. 22, fip;s. 6j 

 10, 10a, I2a-g; pi. 23, figs. 10, 15, 1899. 



Off Fernandina, 25 specimens. 



LYDIPHNIS TRANSLUCENS, new species 



Shell minute, translucent white, the spire flattened, with three 

 moderately rounded whorls; axial sculpture of incremental lines 

 only; spu-al sculpture of a thread slightly in front of the suture and 

 another beyond the periphery on the base; these are hardly promi- 

 nent enough to be called carinae; the umbilical pit is wide and shal- 

 low, the umbilicus itself minutely perforate; aperture rather wide, 

 rounded, oblique, the margin thin, continuous, straight near the umbil- 

 icus. Height, 1.5 mm.; diameter, 2 mm. U. S. Nat. Mus. Cat. 

 No. 108434. 



Off Georgia, two specimens. 



Notwithstanding its small size it has the shell characters of the 

 genus. The incremental lines are rather pronounced. 



LYDIPHNIS HENDERSONI, new species 



Shell small, white, depressed, glassy, with about three tricarinate 

 whorls, the nucleus deeply sunken; axial sculpture of faint incre- 

 mental lines, on the spire retractively oblique and on the base pro- 

 tractively arcuate; spiral sculpture of a prominent carina at the 

 periphery, a less prominent one on the spire about one-third of the 

 way from the suture to the periphery, and on the base another 

 slightly nearer the umbilicus than to the periphery; these two sec- 

 ondary keels are variable, sometimes strong, sometimes almost 

 obsolete, sometimes partly one or the other on the same specimen; 

 the edges of the carina are sometimes finely spirally striated, 

 suggesting that they may when fresh and intact cany a series of 

 epidermal fringes like Episcynia; the space within the basal carina is 

 funicular, extending to a moderately narrow perforate umbilicus; 

 the aperture would be rounded, but in those specimens in which the 



