GASTEROPODA. 37 
Length, zioths of an inch. 
Localities. Cor. Crag, Gedgrave, and Ramsholt. 
The specimen figured was found by myself at Ramsholt, and since the engraving was 
made Mr. A. Bell has shown me some similar and rather better specimens which he has 
obtained from a dealer at Orford. In the ‘Ann. and Mag. Nat. Hist.’ for May, 1871, 
Mr. Bell has described three species under the respective names of Plewrotoma elegantula, 
Pl. volvula, and Pl. notata. 'These specimens I have seen, and although there is some 
slight variation among them, there did not appear to me sufficient differences for specific 
variation. I have here adopted one of the names he has published, but I think from what 
I saw the others can be considered only as varieties. A large series of these is desirable 
to determine their correct claim to specific isolation. Our present shell has 7—8 volutions, 
the two first are smooth and the third has numerous riblets, while the rest of the shell 
has prominent obtuse costae, with fine spiral striae, which are visible only in places. 
PLEvROToMA cRAssA, 4. Bell. Supplement, Tab. VII, fig. 10. 
ConopLeuRA crassa, 4. Bell. Ann. and Mag. Nat. Hist., p. 8, May, 1871. 
Spec. Char. ‘Shell thick, shortly conical, smooth, polished ; spire occupying about 
half the length of the shell; apex pointed ; whorls 8—10 slightly convex at bottom, con- 
stricted towards the top; suture slight, forming a channel on the top of the whorl; ribs 
stout, but hardly raised above the surface; mouth short, open; canal short and broad; 
pillar lip straight, reflected with the callus, massed into a pad at the top, which forms one 
side of the labial notch ; notch very large, broad, and deep ; outer lip spreading.” —A. Bell. 
Length, z5ths of an inch. 
Locality. Coralline Crag, Gedgrave. 
Two specimens of this species have been obtained by Mr. Bell and sent to me with 
the MS. name of Conopleura crassa attached. his specific name I have therefore retained 
for the present, but the generic one, I think, is not required. ‘This shell appears to be 
closely allied, and perhaps when more specimens are examined it may be referred to 
sigmoidea, Broun, figured and described by Bellardi, ‘ Mon. della Pleur. Foss.,’ p. 109, as 
Raphitoma, sigmoidea, Tab. IV, fig. 29; that shell, however, is described as “ Anfractibus 
ventricosis, and finely striated. ‘The Crag specimens appear to be free from strize (judging 
from the two specimens I have seen) with rather flattened volutions. ‘The apex is small, 
‘ut obtuse, and the two first volutions are without ridges. 
