94 SCALARIIDiE. 



broad and semicylindrical, slightly cloven in the middle, and 

 delicately stippled with brown : tentacles gradually tapering, 

 although rather short, margined on each side with a purplish- 

 brown line, and streaked with white underneath : eyes small, 

 round, and black, immersed in bulgings at the outer bases of 

 the tentacles : foot very long and slender, extending far be- 

 yond the head, in front somewhat rounded and with small an- 

 gular corners, bilobed behind ; on the upper side a long fur- 

 row runs from the hinder edge of the operculum to the tail, 

 as in Trochus, with a well-defined ridge on each side of it. 



Shell conical and of about the same proportions as S. com- 

 munis, much thinner than that or the preceding species, opaque, 

 somewhat glossy : sculpture, longitudinal ridges, arranged 

 usually in continuous but oblique rows, as in J8. communis ; 

 they are, however, narrower, less folded, and more flattened, 

 and are occasionally varicose ; the upper part of each ridge is 

 broader and generally (especially towards the point of the 

 spire) expands into a short spur-like projection, so as to give 

 a turreted appearance to the shell ; there are 14 ridges on each 

 of the last two whorls, 13 on the next, diminishing in number 

 upwards ; the interstices of the ridges are delicately and mi- 

 croscopically striated in a spiral direction ; the first 4 or 5 

 whorls are smooth and polished : colour fawn ; the ridges 

 are white : spire tapering to an apparently fine point ; apex 

 as in the last species : wliorls 14-15, convex, increasing 

 gradually : suture deep : mouth considerably more angulated 

 below than above, the pillar being somewhat strait, especially 

 in the young : outer lip thick, formed of the last ridge : inner 

 Up rather thin above, and less connected than usual with the 

 outer lip, thickened and broad below ; behind it is a depres- 

 sion, but no umbilicus : operculum light-horncolour, having 

 about 6 turns, the inner ones being defined by a slightly raised 

 edge ; it is concave in the middle, and marked with coarse 

 flexuous strisG in the line of growth. L. 1. B. 0-4. 



Habitat : Shetland, in 75-100 f. (M'Andrew and 

 others) ; Orkneys, 15-100 f. (Thomas) ; Moray Firth 

 (Gordon) ; Firth of Forth (Gerard) ; northern coasts of 

 England, from Berwick to Scarborough (Johnston and 

 others) ; Macgilligan, co. Londonderry (Thompson); 

 co. Cork (Humphreys and Wright); off Mizen Head 

 and Cape Clear in 50-60 i., and on the Nymph bank 



