mollusca. 
399 
Genus 31.—T CJRBINELLA.— Lamarck. 
Generic Character. — Shell turbinated or sub-fusiform ; with 
a canal at the base; columella with from three to live oblique, 
transverse, and compressed plaits. 
Turbinella pyrum. — The Pear-Shaped Turbinella. 
Plate LXXXV. fig. 8. 
Pear-shaped; yellowish-white, with irregular reddish-brown 
spots; spire short, mucronate; apex mammilliform; beak long ; 
columella with four plaits; in adult specimens, the shell is 
covered with a very thick opaque yellow-brown epidermis. Six 
inches long. Inhabits the Indian ocean. 
Genus 35.—PLEUROTOMA. — Lamarck. 
Generic Character —Shell turrited or fusiform, terminated 
below by a straight canal, of greater or less length; outer lip 
with a notch or fissure at the upper part. 
Pleurotoma nodifera — The Javanese Pleurotoma. 
Plate LXXXV. fig 7. 
Fusiform, turrited; volutions somewhat angulated, upper 
ones smooth; under volutions and body transversely striated 
with angulated oblique nodules at the suture; outer lip deeply 
crenulated, with a large notch ; reddish-yellow. One inch and 
a half long. Inhabits the seas around Java. 
Genus 36. — CE RIT HIUM. — Bruguiere. 
Generic Character. — Shell turrited; aperture oblong, oblique, 
terminated at the base by a short, truncated, recurved canal, 
without a notch ; the outer lip with a groove at its upper ex¬ 
tremity; aperture provided with a small horny operculum. 
Cerithium semigranosum .— The Semigranulated Cerithium. 
Plate LXXXV. fig. 9. 
Fusiform, turrited; apex acute ; transverse minute strise, and 
sulcated granulations; the suture with double spiral rows of 
large granules; colour reddish-brown. One inch and a half 
long. Inhabits the seas of New Holland. 
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