SIGARETUS, Lamarck . 
Gen. Char. Shell univalved, internal, ear 
shaped, suborbicular ; aperture dilated, en- 
tire, rounded, oblong, margin divided, inner 
lip thin; columella spirally curved. 
A Small imperfect almost immersed spire, and a large 
expanded aperture, are common to Stomatella, Hal iotis, 
and several other genera, from which Sigaretus is dis- 
tinguished by the form of its thin inner lip applied close 
upon the spire, leaving a more or less conspicuous um- 
bilicus in a slender columella, that is so united to the 
thick edge of the lip as to appear a continuation of it; 
a considerable portion of the spire is also visible within 
the aperture. The surface is often striated or reticu- 
lated, but has a smooth aspect indicative of its being 
covered by the animal. Only one fossil species appears 
to be known, while there are several recent ones. 
SIGARETUS canaliculatus. 
TAB. CCCLXXXIY. 
Spec. Char. Obovate, convex, longitudinally 
striated; spire pointed, its turns distinguish- 
ed by a canal ; umbilicus large. 
Strongly resembling S. concavus of Lamarck, but 
much smaller, and distinguished besides by its umbili- 
cus. The stiae upon its surface are elevated, often un- 
dulated, and even decussated by the lines of growth : 
it is small and pointed. 
