RISSOA. 129 



in their convexity below, more arched inwartl above. This 

 difference of shelve tends to the better defining of the 

 whorls, which are likewise sep^-ated by a profound but 

 simple suture. The body is rather wide in proportion 

 to its length, and is somewhat shorter than the spire ; 

 its declination is sudden, but rounded ; its axis is more 

 or less perforated. The mouth is suborbicular, and pro- 

 jects both laterally and basally ; the peristome is con- 

 tinuous, but the parietal enamel is but little spread. The 

 outer lip is simple, acute, and much arcuated both above 

 and below. The pillar-lip is likewise arched, though in 

 a less degree, is long, rather narrow, generally rufous, 

 erect, and reflected. The ordinary length of our British 

 specimens is not even two-thirds of a line. 



So far as known this is a southern and western species. 

 It has been taken at Guernsey (Barlee) ; Weymouth ; 

 Falmouth ; Langland Bay near Swansea (Jeffreys) ; Tor- 

 quay (S. H., Clark) ; Burrow Island (Rev. G. M. Beevor); 

 Tenby (Lyons); Arran in Ireland (Barlee); Cork Har- 

 bour and Bantry Bay (Jeffreys). 



R. PULCHERRIMA, Jeffreys. 



Very minute, obovate-conical, umbilicatecl, smooth, witli three 

 or four spiral rows of spots on the body-whorl ; volutions four, 

 ventricose ; spire short. 



Plate LXXXV. fig. 1, 2. 

 Rissoa pulclierrima, Jeffreys, Ann. Nat. Hist, (new series) vol. li. p. S.il. 



This very minute shell has an obovate conical shape, is 

 semitransparent, extremely thin, quite smooth, and of a 

 glossy yellowish white, that is adorned with spiral rows of 

 small and rather distant squarish spots of yellowish or 



VOL. III. s 



