342 MURICID^. 



together, with bluntly pointed tips : eyes small and black, seated 

 on the top of long stalks, about halfway up the tentacles : 

 foot lanceolate, thick, rounded and double-edged in front ; tail 

 either pointed or blunt and somewhat truncated : odontophore 

 long; rhachis square, armed below with a single projecting 

 spine ; pleurae comb-shaped, and deeply serrated. 



SHELL forming a spindle of moderate length, rather solid, 

 nearly opaque, not glossy: sculpture, numerous thread-like 

 spiral ridges, which are alternately large and small on the 

 lower whorls and equal in size on the upper whorls ; there are 

 about 6 of each size on the penultimate and each of the two 

 preceding whorls, and 5 or 6 of the larger size only on each of 

 the next two whorls ; the larger ridges extend to the base and 

 suture ; the surface is also covered with minute and close-set 

 curved longitudinal striae, which by crossing the ridges pro- 

 duce a slight decussation, especially towards the apex ; the 

 first two whorls are smooth and glossy: colour pinkish-white : 

 epidermis rather thick, brownish-yellow, or sometimes fawn- 

 colour, rising into crowded prickly points on the ridges, so as 

 to give a regularly hispid appearance : spire tapering to a blunt 

 point ; apex symmetrical and compressed, resembling that of 

 the last two species : whorls 8, convex and in the middle tu- 

 mid, rather slowly enlarging; the last occupies about two- 

 thirds of the shell : suture deep : mouth oval ; upper corner 

 nearly rectangular ; length (including the canal) about four- 

 sevenths of the shell : canal of moderate length, wide, nearly 

 straight, two-thirds open, ending in a large and obliquely 

 curved notch : outer lip semicircular, flexuous, incurved above ; 

 edge somewhat thickened, reflected, and expanded ; inside 

 pinkish, slightly grooved beneath the larger ridges : inner lip 

 forming a more or less thick glaze (according to the age of 

 the individual), which is spread over a considerable part of the 

 underside of the shell ; it is reflected over the lower part of 

 the pillar and inner side of the canal : pillar curved, slightly 

 angulated at the commencement of the canal : operculum ear- 

 shaped, rather thin, amber or light horncolour, somewhat con- 

 cave, marked with fine and close-set oblique striae in the line 

 of growth and with a few impressed lines which radiate from 

 the nucleus. L. 3-25. B. 1-625. 

 Var. elegans. More slender, and the spire elongated. 



HABITAT : Muddy or soft ground in the coralline 

 zone, on the coasts of Yorkshire and Northumberland ; 



