308 MURICID-E. 



outer and pillar lips, which are ultimately welded together ; 

 it is obliquely truncated towards the base, and terminates out- 

 side in a deep and rounded notch with a thick edge : outer lip 

 nearly semicircular ; that part which consists of the last-formed 

 rib slopes outwards, and is strengthened by a continuation of 

 the spiral ridges ; the edge is slightly prominent ; inside fluted, 

 and furnished with 7 or 8 small tubercles or teeth : inner lip 

 thick, united above with the outer lip ; at the base of the pillar 

 is a groove and umbilical chink, as in Triton cutaceus, but it is 

 much smaller and less distinct : pillar broad and glossy : oper- 

 culum reddish-horncolour, thinner than in the last-mentioned 

 species, irregularly laminated, and microscopically and super- 

 ficially wrinkled. L. 2-25. B. 1-125. 



Yar. sculpta. Spiral ridges much more prominent and keel- 

 like, especially those on the upper part of each whorl, giving 

 the shell a scalariform appearance; space below the suture 

 deeply excavated. 



HABITAT : Stony ground, at low-water mark and in 

 the laminarian and coralline zones, on the southern and 

 western coasts of England and Scotland, and throughout 

 Ireland and Wales; estuary of the Thames (Thomas 

 and J. G. J.) ; trawled off Yarmouth (Rose) ; Scar- 

 borough (Bean) ; Northumberland and Durham (Alder) ; 

 dredged in Berwick Bay, 50 f. (Mennell) ; Moray Firth 

 (Gordon) ; Aberdeen (Macgillivray) . All the specimens 

 procured from the northern coasts were dead. I dredged 

 the variety off Guernsey. M. erinaceus occurs in quater- 

 nary deposits at Strethill (Maw) ; Macclesfield (Darbi- 

 shire); Kelsey Hill (Prestwich); Moel Tryfaen (Darbi- 

 shire and Drury Lowe); Belfast (Grainger); Ireland and 

 Clyde beds ( J. Smith and Forbes) ; " Mammalian Crag " 

 at Bramerton (S. Wood); "Norwich Crag" (Witham, 

 fide Woodward); Italian tertiaries (Brocchi, Scacchi, 

 and Philippi) . Living in the Cattegat (Loven) ; North 

 Atlantic from Boulogne (Bouchard) to Madeira (M f An- 

 drew) and the Azores (Drouet) ; Mediterranean (Linne 



