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CERITHIUM, Bruguiere. 
Gen, Char. Shell univalve, spiral, terminated at 
the base by a short truncated or recurved canal ; 
aperture oblique, with an obscure canal at the 
upper part. 
T he shells of this Genus are generally seven times the 
width of the aperture long, and beautifully ornamented 
by tubercles, transverse striae or carinae and longitudinal 
costae, variously combined and proportioned. It seems 
to be a very natural Genus, containing many species ; 
but the canal at the upper part of the mouth is often very 
obscure, and sometimes, even entirely wanting. The 
size of individuals varies from a quarter of an inch 
to two feet in length, limits which are exceeded by 
very few Genera of spiral shells. This Genus has 
been divided into three by Montfort; how far this di- 
vision may be found necessary by those who are con- 
versant with foreign shells, I will not pretend to say, 
but at present l feel satisfied with Lamarck’s distinctions 
and would wish to go no further. 
GERXTHIUM pyramidalis. 
TAB. C XXVIL— Fig. l. 
Spec. Char. Pyramidal, with six projecting tu- 
berculated angles; whorls 10 or 11, trans- 
versely tri-carinated, carinae tuberculated ; six 
compressed tubercles on the upper part of the 
last whorl; outer lip expanded. 
VOL, II. 
