LACUNA. 61 



the total length of the axis. It is indented near the 

 moderate -sized umbilicus, with a tolerably profound and 

 broad canal, that in general does not extend down to the 

 anterior extremity ; but occasionally does so. The Turho 

 P'uteolus of " Turton's Dictionary," is a sub- variety of this 

 form, in which the shape is more like pallidiila^ being 

 depressed, rounded, and obliquely produced ; the pillar 

 and groove are consequently broader. 



It is by this last modification that we are led into the 

 peculiarly aberrant fasciata, the ordinary northern form 

 of this species. In this variety, the banded colouring 

 is redder, and, for the most part, better defined than in 

 the type, the zones are generally continued upon the 

 penult turn, and the apical whorls are pale or liver- 

 coloured, instead of violet. The shell is thinner, smoother, 

 and glossier ; and the shape, although occasionally pre- 

 cisely that of the type, is usually more obliquely produced, 

 and hence less globular. This alteration in the general 

 contour proportionately affects the several parts likewise. 

 The looser coiling of its whorls, which are rounded and 

 more shelving, causes the spire to become more elevated, 

 so that it occupies nearly two-fifths of the total length of 

 the shell. The pillar-lip is arcuated, narrower, and more 

 elongated than in the type ; it is canaliculated throughout, 

 and its inner margin sharply defined by the overhanging 

 edge of the body whorl. 



Our own specimens scarcely measure a quarter of an inch 

 in either direction ; but Turton's are stated to have been 

 nearly half an inch across. 



The animal, in such specimens as we have taken alive, 

 is entirely of a pale yellow or tawny colour, with the 

 exception of two dusky dots or lines on the top of the 

 muzzle. The head is rather large, with a prominent and 



