AKT. 18 SMALL SHELLS DREDGED BY " ALBATROSS '^ DALL 53 



ASTYRIS PERLUCIDA, new species 



Shell minute, slender, white or yellowish, thin, with an inflated 

 smooth nucleus of a whorl and a half and about three subsequent 

 whorls; suture distinct, not appressed; whorls moderately rounded, 

 smooth except for very fine regular incremental lines only visible 

 with a lens; there are very faint spiral striae on the base and back of 

 the canal; aperture sublunate, outer lip thin, simple, body enameled, 

 pillar straight, canal distinct, slightly recurved; axis minutely or not 

 at all pervious. Length of shell, 5; of aperture, 2; diameter, 2 mm. 

 U. S. Nat. Mus. Cat. No. 108001. 



Off Fernandina, about 20 specimens. 



Similar to A. pura but with rounder, thinner, and more translucent 

 whorls, and somewhat more eleva-ted spire. 



ASTYRIS STEMMA, new species 



Shell small, slender, white, with a small blunt white nucleus of 

 about one whorl and five subsequent rather flattish whorls; suture 

 distinct, not deep; axial sculpture of obscure incremental lines; there 

 is no spiral sculpture; in front of the suture the edge of the succeeding 

 whorl is very slightly and narrowly turrited; the base is gradually 

 attenuated; aperture short, semilunate; the outer lip thin, smooth, 

 nearly vertical; the body without glaze, the pillar short and twisted; 

 the axis minutely pervious. Length of shell, 6; of aperture, 2; 

 diameter, 2 mm. U. S. Nat. Mus. Cat. No. 108003. 



Off Fernandina, abundant. 



This is more elongated than either of the others. 



Section FLUEIIA Dall 



Like Astyris but spirally sculptured without conspicuous axial 

 sculpture. 



ASTYRIS (FLUELLA) VIDUA Dall 



Astyris {Fluella) vidua Dall, Proc. Biol. Soc. Wash., vol. 37, p. 87. 1924. 



Shell small, thin, translucent white, with an inflated, smooth nucleus 

 of a whorl and a half, and about three subsequent well-rounded 

 whorls; suture distinct, not appressed; axial sculpture only of faint 

 incremental lines; spiral sculpture of numerous equal and equally 

 spaced spiral striae covering the whole shell but stronger on the last 

 whorl; aperture semilunate, outer lip thin, simple, a slight swelling 

 behind it; body with a thin layer of enamel; pillar short, slightly 

 recurved; canal hardly differentiated from the aperture, axis pervi- 

 ous. Length of shell, 4; of aperture, 1.7; diameter, 2.5 mm. U. S. 

 Nat. Mus. Cat. No. 108002. 



Off Fernandina, abundant. 



This may be taken as the type of the new section. 



