224 
growth, which are particularly strong over the base, run- 
ning into the large umbilicus in plails. External lip obtuse, 
internal sharp, about half extended over the base of the 
spire. The undulated margin seems the part mostly de- 
signed for collecting shells, &c. 
This is one of those few fossils which agree so well with 
analogous recent shells, that they can with difficulty be 
distinguished as varieties. ‘The American shell commonly 
styled ‘‘ the Carrier,” is so nearly allied, that Delamarck 
says he could not distinguish it. Our specimens are from 
Barton. 
TROCHUS Benettiz. 
TAB. XCVIII.— Larger figures. 
Spec. Cuar. Depressed, conical; upper surface 
obliquely wrinkled ; base expanded with a broad 
waved margin; whorls, externally irregular ; 
umbilicus plicate, partly covered; aperture 
narrow. 
SBM eas RR ted 
The obliquely striated or wrinkled surface, which bears 
some resemblance to the rippling of shallow water, marks 
this as decidedly distinct from the last; in other respects, 
what has been said of that will apply correctly to this. The 
umbilicus being partly covered by the lip is the eect of 
age. The spire is less irregular than usual. 
This elegant specimen is in possession of Miss Benett, 
who has been so fortunate in meeting with many rarities. 
It would have been a great satisfaction to have met with it 
without the aperture being crushed in, which makes it 
more difficult to comprehend. This is, however, sufliciently 
distinct to be recognized as a species, and perhaps we may 
never see such another: I have therefore named it in honour 
of its possessor. 
