18 rROCEEDINGS OF THE NATIONAL MUSEUM. vol.56. 



If the specimen is not quite mature the aperture may prove to be 

 more elaborate in the adult. The shell is intermediate in type be- 

 tween Suavodrillia and Clathrodrillia. The soft parts being absent 

 the presence of an operculum is tentatively assumed. 



CLATHRODRILLIA (CARINODRILLIA) ALCESTIS, new species. 



Plate 5, fig. 6. 



Shell slender, acute, pale yellowish brown (the nucleus lost), with 

 about ten whorls; suture strongly appressed with a prominent cord 

 (afterwards broadening into a band) in front of it; siphonal fasciole 

 constricted ; with only arcuate striation ; sculpture on the early whork 

 of two or three strong cords, swollen where they override the ribs, 

 these are prominent on the periphery ; on the later whorls the periph- 

 eral cord becomes an undulated keel and the interspaces are closely 

 spirally striate; on the last whorl in front of the keel are about a 

 dozen major threads with wide spirally striate interspaces; axial 

 sculpture of (on the last whorl seven) peripheral waves, rather than 

 ribs, overridden by the spirals, the incremental lines inconspicuous; 

 aperture narrow, anal sulcus slightly removed from the suture, dis- 

 tinct, with a small subsutural callus; outer lip moderately produced, 

 sharp edged, slightly crenulate by the spiral sculpture, smooth with- 

 in; inner lip with a moderate layer of callus, with slightly raised 

 outer edge which is continued over the pillar and on the canal is sepa- 

 rated from the feeble siphonal fasciole by a narrow chink; canal 

 short, wide, slightly recurved. Height of shell (without the nu- 

 cleus), 30; of last whorl, 16.5; diameter, 8 mm. Cat. No. 212354, 

 U.S.N.M. 



Range. — Station 3037, off Guaymas in the Gulf of California in 20 

 fathoms green mud. IT. S. Bureau of Fisheries. 



CLATHRODRILLIA (CARINODRILLIA) THESTIA, new species. 



Plate 5, fig. 3. 



Shell slender, acute, strongly sculptured, with pale brownish cloud- 

 ing on a yellowish white ground ; nucleus smooth, inflated, of a whorl 

 and a half, followed by about eight sculptured whorls; suture dis- 

 tinct, undulated, strongly appressed, thick-edged, with a strong cord 

 immediately behind the stronglv constricted smooth anal fasciole; 

 other spiral sculpture of (on the spire one or two) strong peripheral 

 cords, swollen and almost angulated where they override the ribs; 

 on the last whorl there are six or seven cords with much wider in- 

 terspaces and as many more smaller close-set threads on the canal ; ax- 

 ial sculpture of seven or eight very prominent short ribs on the penul- 

 timate whorl; fading out on the last whorl, and rather prominent 

 widely spaced incremental lines most conspicuous on the last whorl; 

 aperture subovate, anal sulcus conspicuous, rounded, with a marked 



