NATICA. 215 



covered with the epidermis ; base somewhat attenuated and 

 angular: sculpture, apparently none; but the lens discloses 

 numerous slight spiral striae, irregularly disposed and often 

 wavy ; by the aid of a microscope may also be seen much more 

 numerous and still finer lines of growth, which, however, do 

 not produce any decussation of the surface : colour milk-white 

 under the epidermis, which is pale-yellow or lemon- colour in 

 young specimens, brownish-yellow in the adult : spire turreted, 

 abruptly and bluntly pointed : whorls 5-7, rounded but com- 

 pressed ; the last occupies nearly five-sixths of the spire ; the 

 first is very minute, and scarcely projects beyond the second : 

 suture rather oblique, deeply and conspicuously channelled or 

 grooved inwards, so as to leave a narrow ledge at the top of 

 each whorl and to give the appearance of their partly over- 

 lapping one another: mouth equal in area to one- third of the 

 shell, and in length to two-thirds of the spire, expanding and 

 somewhat angulated at the base : outer lip incurved above, and 

 joining the inner lip, which is spread over the pillar and almost 

 conceals a narrow and small umbilicus : operculum thin, golden- 

 yellow, minutely, very finely, and closely striated in the line 

 of growth ; whorls 4, defined by a raised edge or rim, the last 

 disproportionately large. L. 1. E. 0-65. 



HABITAT : Rare, in the coralline zone, from 7 to 79 f., 

 Shetland (Barlee, M'Andrew, and J. G. J.); Orkneys 

 (Thomas) ; Wick (Peach) ; Aberdeen shire (Macgillivray, 

 Gordon, and Dawson) ; Banff (Edwards) ; Firth of Forth 

 (Knapp); Berwick Bay (Johnston); Northumberland 

 coast (King) ; Sunderland (Howse) ; Scarborough (Lec- 

 kenby); Cork (Humphreys). In most of these cases 

 the specimens were caught by fishermen, or taken from 

 the stomachs of haddocks. It occurs in most of our 

 quaternary or post-glacial beds in Scotland, Ireland, 

 and Yorkshire; Norwich and Red Crag (Lyell and S. 

 Wood); Uddevalla (Lyell and others); Christiansund, 

 30-40 feet (Sars) ; Gardiner, in the State of Maine 

 (Lyell). Recent in Scandinavia, Iceland, Faroe Isles, 

 coasts of Russian Lapland and the White Sea, Spitz- 

 bergen, Greenland, Massachusetts northwards to Canada, 



