138 
MOLLUSCOUS ANIMALS. 
NERITOPSIS. GRATELOUP. 
Animal and operculum unknown. 
Neritopsis radula. 
Nerita radula. Born. t. 17. /. 78. — Cliem. v. /. 1946,47. — Wood, Cat./. 23. 
Inhab. Indian Ocean. 
This species is also found fossil, and there are two or three other species. They are all known by the 
nick, out of the middle of the inner lip. 
VELUTINA. 
The foot lanceolate, moderate, double in front; tentacles short, compressed, rather distant at their base, 
with a slight crest between them ; eyes on the outer side of the tentacles near the base ; penis on the right 
side, large, like that of Buccinum in shape, with subapical conical tip ; operculum none. 
STYLINA. Fleming. 
It appears from the slight examination that I have been able to make of the animal of this genus, that what 
is called the mantle in Mr. Broderip’s character of this genus is rather the foot. 
Dr. Fleming places the English species in Velutina, but proposes to establish this genus under the name 
of Stylina; therefore I have adopted it in preference to the one since proposed by Mr. Broderip of Stylifer. 
There is a great alliance between this genus and the Helix polita of Montagu, which forms the genus 
Eulima of Iiisso. It is remarkable that both the genera are very apt to be curved. 
LITTORINA. 
The tentacles subulate, rather distant ; the eyes rather prominent on the outer base of the tentacles ; the 
operculum horny, ovate, spiral, of a few, very rapidly enlarging whorls. 
The animals inhabit the sea coast between the high and low water marks where they are often left dry for 
many hours. 
The colour of the animals of the common English L. retusa agrees with the colour of the shell : thus the 
orange shells have orange inhabitants, and the dusky ones dusky ; they are always of an uniform colour, while 
the animal of the L. vulgaris is always varied with black lines. 
Littorina irrorata, t. 38./. 1. 
Turbo irroratus. Say. 
Pbasiaiiella sulcata. Lam. 
Shell obovate, conical, solid, whitish, brown dotted, spire conical, apex acute, brown ; whorls closely 
spirally grooved, close together in front and wider apart near the sutures. Mouth ovate; columellar lip 
yellow brown; throat white ; outer lip thickened internally, with two rows of brown dots near the thin part of 
the outer edge. Axis 1 inch ; diam. 8 lines. 
Littorina Peruviana, t. 36./. 8. 
Phasianella Peruviana. Lam. Hist. vii. 53. 
Turbo Zebra. Wood. Cat. Sup. t. 6./. 33. 
Littorina striata. King, Zool. Journ. 
