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ROSTELLARIA, De Lamarck • 
Strombus 3 Linn , 
Gen. Char. A fusiform or subturretted univalve, 
with the base drawn out into a sharp canal i- 
culated beak; the lip expanded bj age, either 
entire or toothed, with a sinus close to the 
beak, and an elongation upon the spire. 
Although there are many recent species of this Genus, 
we are acquainted with but few fossil ones. It is one of 
the Genera made by De Lamarck out of the Linnean Genus 
S trombus, its principal character being the indentation of 
the lip close to the beak. In some species the upper edge 
of the lip is extended in a canal nearly the whole length 
of the spire. 
ROSTELLARIA? lucida. 
TAB. XCl—Figs. 1, 2, and 3. 
Spec. Char. Fusiform, longitudinally ribbed, trans- 
versely striated; lip thick with an obscure sinus 
at the inferior edge, and a very short channel at 
the superior; beak straight, short? 
The surface of this species is glossy and covered equally 
with fine rising obtuse striae, the ribs numerous and rounded, 
the whorls about eight, in the young shell the lip is not 
thickened; when the last whorl is about half-formed its 
growth is stopped, and the edge of the lip is inflected ; it 
afterwards grows to its full size, and the lip thickens, 
leaving the inflected part of the former lip in the form of a 
large rib about half a whorl from the end. The beak is not 
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