xlv 
Ascaris, f. 20 ( p). Turbiforme, 193. 
CERITHIUM. Tuberculare, 193, f. 8. 
Costatumn, 196. Reticulatum, 193. 
narrow Jongitudinal ribs, which are about one third of 
the breadth of the interstices, and a single raised 
spiral rib situated a little below the middle of each 
whorl; two additional rather indistinct lower ones on 
the body whorl, which occupies one third the length of 
the shell. %...dreadth two fifths of length. Guernsey. 
This mast beautiful species, from the upper portion of 
the whorls being flattened, seems in a fine specimen to 
have the ribs tuberculated at their summit, or when 
rubbed, even to form a spiral band there. The aperture 
is small and squarish ; there is no umbilicus but in per- 
fect specimens, a slight umbilical groove and a very in- 
distinct plait on the eolumella, but not the contracted 
mouth of Odostomia. 
(p) Turso Ascaris, Turét. Dic. 217. Extremely 
slender, tapering to an exceedingly fine point, milk 
white, semitransparent ; whorls 7 or 8, rounded and 
well defined by a deep impression, each with 4 or 5 
regular equidistant and rather deep spiral grooves ; 
aperture suborbicular, the inner lip a little reflected. 
Breadth a fourth of the length, which is not the tenth 
of aninch. Seafield Ireland. Rare. 
