20 



Remarks. In the older specimen the sculpture is not so clearly visible as in the 

 younger one. The chalky and dark brown deposit in the oldest specimen renders the cancellated 

 character less striking, even quite invisible on some parts. Both specimens show an extremely 

 deep circular incision where a broken peristome has been repaired. 



D. hibiformc is much finer cancellated than D. caucellatmn and there are no secondary 

 riblets as in that species. 



*i8. DentaliuDi canccllatHiu .Sowerby. PI. I, fig. i6. 



i860. Dcntaliuin canccllatimi Sowerby, Thes. Conch. Ill, p. 101, pi. 224, fig. 36. 



1872. Dentaliuin cancdlatuui Sowerby, Concli. Icon. XVIII, pi. 5, fig. 29. 



1897. Dentaliuin cancellatuni Sowerby. PiLSBR'i' & Sharp, Man. of Conch., vol. XVII, p. 30, 

 pi. ID, fig. 6-j. 



Diagnosis. .Shell thin, white, acuminate, strongly curved towards the apex, where it is 

 cancellated by about 8 longitudinal ribs and elevated concentric striae, then the shell becoming 

 straighter and the ribs more numerous (.Sowb.). 

 Length 25V;, greatest diam. 3 mill. (P. & S. from fig.). 



Distribution. China Sea. 



19. DcntaUinn orvx n. sp. PI. VI, fig. 24. 



Stat. 302. 10° 27.9 S., 123° 28'. 7 E. 216 Metres. Sand and coral sand. 5 Spec. 



Diagnosis. Shell straight or only with a faint curve at the top. Sculpture of 8 narrow 

 riblets at the apex, increasing to double that number by intercalation 

 of secundary riblets and doubling again that number by renewed inter- 

 calation of tertiary riblets. Interstices faintly concave, without longitudinal 

 or transverse sculpture. Ribs persistent toward the anterior aperture, 

 their profile irregularly undulated. 



Anal orifice with a short wide incision. Anterior aperture distinctly 

 octagonal, not oblique. Colour white or bluish white, a little transparent. 



Fig. 14. Anterior aperture 

 and apex of D> orvx. 



a. Length 26 mill., greatest diam. 2 mill. 



b. Length 20 mill., greatest diam. 1,8 mill. 



c. Length 27 mill., greatest diam. 2,2 mill. 



20. Dentaliuin leucoryx n. sp. PI. VI, fig. 23. 



Stat. 2S5. 8° 39. 1 S., I27°4'.4E. 34 Metres. On the limit between mud and coral. 3 Spec. 



Diagnosis Shell moderately curved, white, shining and transparent 

 in young individual. Sculpture of eigth narrow rounded riblets at the apex, 

 soon increasing to double that number by intercalation. Ribs persistent 

 toward aperture in the voungest individuals, becoming a little obsolete in 



tig. 15. .•interior aperture ..." 



and apex of D. leucoryx. the older individual. The profile of the ribs is irregularly undulated, due to 



