10 DENTALIUM, 



Katoio, Nero Guinea, 8 fathoms, sandy mud and coral (Chevert 

 Exped.). 



A white species with 14 ribs on the base, having 7 at the apex 

 more defined (Braz.). 



D. hatoxvense Braz., P. L. S. N. S. W, ii, p. 56 (1877). 



D. ARATORUM Cooke. Unfigured. 



Shell solid, pale amber-colored, acuminate, arcuate, not very 

 strongly but distinctly fluted with 11 or 12 ribs, the interstices and 

 some of the ribs themselves longitudinally strongly lineated, im- 

 pressed interstitial lines about 4 ; apex entire. 



Length 1*5, width at base 0'15 inch (Cooke). 



Gulf of Suez, 10-30 fras. (MacAndrew). 



"D. belcheri Sow. [arato7nim Cooke] " Cooke, Annals and Mag. 

 Nat. Hist. (5), xvi, pp. 274, 275 (Oct. 1885).— D. reevii Desh., 

 MSS., MacAndrew in coll. Not D. reevei Dh,, Fischer ! 



Very distinct from D. lineolatum Cooke, which it nevertheless 

 strongly resembles in its sculpture. This shell is more curved, the 

 ribs are never less than eleven, and are comparatively obscure, 

 while in lineolatum there are always nine, and they are very marked 

 and prominent (Cooke). 



MacAndrew perceived that "Belcheri Sow." was wrong, and has 

 corrected to "Reevii Desh. MSS." I have no idea what this refers 

 to, so will describe the species, which is a good one (Cooke). 



D. LAQUEATUM Verrill, PI. 7, figs. 1, 2 (immature) ; pi. 5, fig. 73. 

 Shell rather large, thick and strong, moderately stout, gradually 

 tapered, gently curved, chiefly behind the middle. The sculpture 

 consists of about eleven [9 to 11] strong, prominent, broad, obtuset 

 longitudinal ribs, separated by deep, concave interspaces, which are 

 wider than the ribs in the middle of the shell and of about the same 

 breadth posteriorly ; at about the anterior third the ribs decrease in 

 prominence, fading out, or becoming flattened into mere obtuse 

 angles at the anterior end ; along the middle of the shell a smaller 

 rib [or two] intervenes between part of the larger ones; four of the 

 ribs on the convex side are closer together and narrower than the 

 rest, while those on the concave side are widest apart. Between 

 the ribs the whole surface is covered with regular, fine and close, 

 microscopic longitudinal lines, which also cover the ribs where they 

 are not worn. Distinct and rather close lines of growth cover the 



