DENTALIUM. 9 



D. TASMANIENSIS Tenison-Woods. 



Shell small, solid, white, slender, slowly increasing, slightly 

 curved ; equally 8-ribbed, the intervals often subcostate ; apex en- 

 tire. Length 10*5, diam. 1/5, diam. of apex 0*5 mill. (T.-W.'). 



Northwest coast of Tasmania (W. F. Petterd). 



D. tasmaniensis T.-W., Papers and Proc. and Rep. Roy. Soc. Tas- 

 mania, for 1876, p. 140 (1877). 



Evidently a member of the D. octangulatum group. " This is a 

 gracefully tapering shell, curved slightly, with valid ribs and often 

 smaller ones in the interstices." 



D. aratum Tate and D. nanum Hutton, of the South Australian 

 and New Zealand tertiaries respectively, are allied species of this 

 group. 



D. WELDIANUM Tenison-Woods. 



Shell small, subcylindrical, shining, whitish, somewhat pellucid ; 

 slightly curved ; obsoletely equally ribbed ; apex entire. Length 

 (decollated) 10, diam. 1*5, diam. of apex 1 mill. (T.-W.\ 



North coast of Tasmania (W. F. Petterd). 



D. iveldiana T.-W., Papers and Proc. and Rep. Roy. Soc. Tas- 

 mania for 1876, p. 140 (1877). 



An almost cylindrical shell, subpellucid and shining, with obso- 

 lete ribs (T.-F.). 



D. CHEVERTI Sharp & Pilsbry, n, n. 



Shell white, slightly arched, 7-ribbed, ribs somewhat sharp, having 

 finer ones between, extending from the base to the center, interstices 

 with fine transverse silk-like striae; apex perforated, perforation 

 with a minute notch-like fissure on the dorsal margin ; aperture cir- 

 cular, entire. Length, 7 lines; diam. apex, I ; base,! lines [14, 

 0-5, 1-5 mill.] (raz.). 



Evans 1 Bay, CapeYork, north Australia, 6 fathoms, sand (Chevert 

 Exped.). 



D. septemcostatum BRAZ., P.L. S. N. S. W., ii, p. 57 (1877). Not 

 D. septemcostatum Abich, 1859. 

 D. KATOWENSE Brazier. 



Shell white, thin, transparent, slightly arched near the apex ; 7- 

 ribbed, from the center to the base 14, those above being most con- 

 spicuous ; interstices with minute lengthened striae ; apex thickened ; 

 perforation small, entire; aperture circular. Length, 7 lines ; diam. 

 of apex, J ; base, 1 line (Brazier'). 



