139 
TROCHUS Gibsi. 
TAB. CCLXXVITI.— Fig. 1. 
Spec. Cuar. Conical, short, umbilicated; sides 
straight ; edge obtusely carinated ; base con- 
vex, reticulato-striated ; in the centre of the 
upper part of the whorls is an elevated band 
crossed by curved striz ; aperture rhomboidal. 
EEE 
Tas shell is wider than it is high: the upper part is 
smooth, except the concentric band, upon which are 
semicircular striz, indicating a sinus in the outer lip. 
The umbilicus is large, and nearly smooth ; and although 
the inner lip of the mouth is a little reflected over the 
columella, which is thin, it has no tendency to close it. 
A cast in pyritiferous Clay mixed with Sand; found 
at Folkstone. This and several other shells, hitherto 
called Trochi, with the band around the spire, may more 
properly belong to the genus Pleurotomaria, which 1 
may be induced at some future period to adopt. I have 
named this after Mr. Gibs, well known for many years 
as a worthy assistant to several collections of British 
shells. 
/¢ shah <A 2 
