232 SOLARIID^E. 



and having very little gloss : sculpture, strong and prominent, 

 but narrow, spiral ridges, of which there are 6 on the body- 

 whorl, 2 on the next, and none on the upper two whorls, 

 which are quite smooth and polished ; the ridges on the body- 

 whorl are thus disposed, 1 close to the sutural line, 2 below 

 it, 1 on the periphery, and 2 encircling the base ; the inter- 

 stices of all the ridges are crossed by numerous longitudinal 

 striae, which are sometimes curved or flexuous ; there are also 

 still more numerous microscopical lines that traverse the 

 whole surface obliquely ; the effect of all these markings is an 

 exquisitely beautiful ornamentation : colour white, with some- 

 times a yellowish- or reddish-brown stain, apparently the re- 

 mains of an epidermis : spire extremely short : whorls 3|-4, 

 compressed, rapidly enlarging ; the upper part of the body- 

 whorl slopes towards the peripheral ridge, which forms a sort 

 of keel ; this whorl, viewed with the mouth downwards, oc- 

 cupies more than two-thirds of the spire : suture well denned, 

 but not deep, in consequence of the upper part of each whorl 

 shelving towards the next: mouth large, indented by the 

 ridges : outer lip projecting far beyond the other lip, rounded 

 and sharp-edged ; upper angle or corner acute : inner lip re- 

 flected on the upper part of the base (where it joins the outer 

 lip) and slightly over the umbilicus, thickened and angulated 

 on the under side, below which it makes a straight course 

 outwards, where it ends in a small notch ; this is very con- 

 spicuous when the shell is held on one side, with the spire 

 from the observer : umbilicus rather large, obliquely sloping- 

 inwards, denned by the lower basal ridge, and striated length- 

 wise, more strongly as the shell advances in age : operculum 

 thin, obliquely striated in the line of growth ; spire extremely 

 small, comprising several minute and close-set turns, and not 

 unlike that of the operculum of a Natica ; the outer whorl is 

 disproportionately large. L. O04. B. 0-1. 



HABITAT : Laminarian and coralline zones, Sandwich 

 (Walker and J. G. J.) ; Dover (Lyons, fide Montagu) ; 

 Dorset, Devon, Cornwall, and Bristol Channel (Mon- 

 tagu and others) ; Guernsey and Barmouth (J. G. J.) ; 

 Irish coasts (Turton and others) ; Lamlash Bay, Bute 

 (Norman) ; Aberdeenshire (Dawson). Red and Coral- 

 line Crag (S. Wood) ; Belgian tertiaries (Nyst, as A. 

 supranitida) ; Dax (Basterot) ; Martillac (Grateloup) ; 



