192 AURICULIDiE. 



Shell varying in shape from subfusiform-oval to oblong- 

 conical, more or less solid, of an uniform ivory white 

 beneath the pale yellowish horn-coloured skin, smoothish, 

 or faintly wrinkled lengthways. Whorls six or seven, 

 simply and only slightly convex, tapering above ; the first 

 four of slow increase, the penult, and occasionally the ante- 

 penult, rather suddenly enlarging ; divided by a fine, and 

 only moderately slanting, suture ; the apex small, but not 

 acute, rather obliquely coiled. Body filling from two- 

 thirds to three-fifths of the dorsal length, sometimes a little 

 ventricose above the middle ; its basal declination gradual, 

 not much rounded. Aperture usually occupying about 

 four-sevenths of the ventral length, reversed semiovate, 

 peaked above, narrowly rounded below. Outer lip simple, 

 sharp, subarcuated, not much if at all expanded, except 

 that it is a little effuse anteriorly, perfectly unarmed ; 

 throat quite smooth. Inner lip with only two folds, a 

 very oblique one at the lower extremity of the columella, 

 and a very prominent and comparatively horizontal one 

 rather below the middle ; not denticulated nor otherwise 

 armed on the upper or parietal portion. Pillar lip ap- 

 pressed ; no umbilical chink. Length of a very large 

 individual a quarter of an inch ; its breadth a line and a 

 half. Variety alba * narrower in its aperture and general 

 shape ; spire consequently more produced ; lower fold 

 often nearly obsolete. 



* The Valuta alba of the first volume of the " Testacea Britannica " (p. 235), 

 and the Jaminia ulba of Brown (111. Conch, p. 22, pi. 8, f. 18), seem derived 

 from figure Gl of Walker and Boys' thin quarto, which appears to represent 

 the Cylichna obtusa. A very different shell, said to have been found by Laskey 

 in Dunbar sand, is described as V. ulba, in Montagu "s "Supplement " (p. 102). 

 It was probably a minute foreign Marginella, but is not so defined that the 

 species can be satisfactorily identified, being merely characterised as minute, 

 ,\ an, with a slightly raised (worn) spire of probably three or four turns, a narrow 

 mouth open below, as in M. pallida, yet not shaped as in that shell, and a pillar 

 with four folds, besides some alight denticulations above them. 



