33 
HELICINA, Lamarck. 
Gen. Cuar. Shell subglobose, without an um- 
bilicus; Aperture entire, semi-ovate; Colu- 
mella callous, flattened at-the lower part. 
HELICINA compressa. 
TAB, X.—Three middle figures. 
Spec Cuar. Spire flattish, an elevated thread sur- 
rounding the upper part; Mouth a little angu- 
lar above. 
Diameter about half an inch, height about one-third of 
an inch, shell very thick and strong. i 
I was favoured with this specimen from Leicestershire, 
by Mr. Milne, F.L.S. it is in a dark coloured Limestone, 
and has the outside of the shell very perfect; the callous 
columella taking place, as it were, of the umbilicus, is very 
curious, and remarkably well preserved for a shell which 
is so completely mineralized. I am not sure that this will 
quite agree with Lamarck’s Genus Helicina, and indeed he 
himself seems very doubtful whether the species he has 
given, and calls dubia, really belongs to it. 
