ART. 18 SMALL SHELLS DREDGED BY ''aLBATEOSS" DALL 55 



spire, and very fine close well-marked incremental lines; aperture 

 narrow, outer lip varicose with five or six denticles within, body with 

 a thick coat of enamel, pillar short, canal very short, but recurved. 

 Length of shell, 6; of aperture, 3; diameter, 3 mm. U. S. Nat. Mus. 

 Cat. No. 108326. 



Off Georgia and Fernandina, nine specimens. 



The prominent characteristic of the typical shell is the way the 

 rotundity of the whorls is suppressed so as to indicate a smooth 

 spindle shape for the whole shell. 



A variety ? (333458) from the same station is more slender, and 

 has the upper whorls nearly smooth and the threads on the last whorl 

 coarser and the varix less prominent. 



Section PLECTARIA Dall 1924 



Like Astyris but with predominant axial sculpture. 



ASTYRIS (PLECTARIA) CRUMENA Dall 



Astyris (Plectaria) crumsna Dall, Proc. Biol. Soc. Wash., vol. 37. p. 87, 

 1924. 



Shell short, small, stout, white, with an inflated translucent nucleus 

 of a whorl and a half and about three subsequent whorls; suture 

 distinct, not deep, whorls well rounded, rapidly increasing; axial sculp- 

 ture of (on the last whorl about 14) rounded ribs, crossing the whorl, 

 with wider interspaces; spiral sculpture of numerous fine equal 

 threads equally distributed over the whole whorl and not nodulous 

 where they cross over the ribs; aperture ovate, outer lip simple, 

 varicose; body with a wash of enamel, pillar short, canal wide and 

 short, not recurved; axis minutely pervious. Length of shell, 4; di- 

 ameter, 3 mm. U. S. Nat. Mus. Cat. No. 108006. 



Off Fernandina, three specimens. 



These shells on account of their axial sculpture were formerly re- 

 ferred to Anachis the type of which is Columhella scalarina Sowerby, 

 which obviously can not be associated with shells of the present group, 

 of which the above species may be taken as type. They are clearly 

 related closely to Astyris, of which the type is C. rosacea Gould. 



ASTYRIS (PLECTARIA) EMBUSA, new species 



Shell small, stout, white, with a large smooth polished nucleus of 

 a whorl and a half, and about four subsequent whorls; suture deep, 

 not appressed, whorls very rotund; axial sculpture of (on the last 

 whorl about a dozen) strong narrow rounded ribs with wider inter- 

 spaces, crossing the whorls; spiral sculpture of numerous equal and 

 equally distributed fine threads with narrower interspaces, not swol- 

 len where they pass over the ribs, and visible over the whole shell; 

 last whorl much the largest; aperture rather short and wide, a glaze 



