305 



DESCRIPTIONS OF A NEW ZEBINA AND A NEW LIOTINA. 



By J. R. i.E B. TOMLIN, M.A. 



(Read before the Society, July :7th, 191?). 



Plate X. 



Zebina Mis sp. nov. (Plate X., fig. 3). 



Ver)^ similar in most ways to Rissoina enieles M. and S. {/onrn. 

 of Cotich., viii., p. 307, plate xi., f. 63), but more cylindrical, narrower 

 at the base, -and less fusiform ; it is also perfectly smooth, lacking 

 the spiral lirations of this species, and has the suture quite flat. 



Alt., 6 "5 mm. ; diam. max., 3 mm. 



Hab., Lifu ; Oshima, Japan (Hirase, no. 193). 



Type from Lifu in my own collection. 



Liotina cycloma sp. nov. (Plate X., figs, i, 2). 



Shell solid, subdiscoidal, slightly convex above, white ; umbilicus 

 narrow, but open to the apex ; whorls 5^- in number, increasing 

 rapidly in size, with a protoconch of i^ whorls, smooth ; the rest of 

 the shell sculptured with very fine, closely packed axial lamellae; 

 there are six spiral cords— one immediately below the suture, orna- 

 mented with a series of numerous sharp-pointed cogs, one on the 

 shoulder of the whorl bearing blunt tubercles, which more or less 

 correspond to the cogs above, two very strong ones on the periphery, 

 one tubercled cord below the periphery, and one cogged cord at the 

 margin of the umbilicus. The peripheral cords are connected at 

 regular intervals of about half-a-millimetre by solid, strongly-raised 

 cross pieces, which are more or less M-shaped if the shell be viewed 

 edgewise and are rather suggestive of the endless chain of buckets 

 on a steam-dredger. The supra-peripheral cord gradually disappears 

 in ascending the spire. Aperture circular, guarded by a strong out- 

 standing varix, on which the spiral cords appear as simple or 

 occasionally bifid ridges. 



Alt., 4 nmi. ; diam. max., 7 "5 mn^ 



Hab., Oshima fHirase, no. 273). 



Type, in my own collection. 



I A-t?, smooth. 



