PULMONATA. 135 
Scymnia, Leach, 1819. 
Stunra, Risso, 1826. 
Carpurna, Fleming, 1828. 
Vouva, Fleming, 1828. 
Cypreiia, Swainson, 1840. 
CartngEa, Swainson, 1840. 
Sect. Votva, Bolten, 1798. 
Ravivus, Montf., 1810. 
Rapivus, Schum., 1817. 
Brrostra, Swainson, 1840. 
Gen. Char—Shell ovate, gibbous, more or less attenuated or produced, and 
emarginate at each extremity ; smooth, convolute upon a nearly horizontal plane ; spire 
concealed : aperture longitudinal, elongated, narrow behind, more expanded in front ; 
outer lip generally inflected, thickened, denticulated ; inner lip smooth. 
The Ovule present great similarities to the Cypreeee, both in the organization of the 
animal and the construction of the shell. The principal distinctions between the 
animals appear to be in the condition of the muzzle, and in the mantle, the surface of 
which, in the true Ovule, is always smooth. The shells are distinguished by the 
absence of teeth on the left-margin of the aperture, and by the prolongation of the 
two extremities ; but, like the Cowries, they are, when fully formed, smooth and polished, 
owing to the enamel-like coating secreted by the extended margins of the mantle. 
The genus was first separated by Gronovius, underthe name Amphiperas, and was 
afterwards defined by Bruguicre under the present name, by which it has been generally 
received. Several dismemberments have been proposed by Bolten, Fleming, Leach, 
Swainson, and others, on conchological distinctions only. In one of these, the genus 
Volva proposed by Bolten for the well-known oriental shell, called the ‘“ weaver’s 
shuttle,’’(Ovu/a volva),the animal, according to Mr.Adams,* presents certain peculiarities, 
consisting of a row of nipple-like tubercles along the edge of the mantle, and of a 
narrow foot folded longitudinally and adapted for crawling upon the round slender 
stems of the Gorgoniz and other zoophytes on which the animal feeds, which modifi- 
cations appear to confirm the separation; but the other proposed divisions are for 
the present received as sections only of the present genus until more accurate knowledge 
of the anatomy and habits of the animals is acquired. 
The living Ovu/e are not very numerous. and are, for the most part, inhabitants of 
warm climates ; they are found principally in the seas of China, Western America, and 
the West Indies ; one species only is found on our own shores. ‘The fossil Ovw/@ are 
very few; seven species from the cretaceous formations, five of which were described 
as Cypree, are referred by D’Orbigny to this genus; two species, exclusive of 
O. (Cyprea) tuberculosa, before described, occur in the Eocene tertiaries of France, and 
three are found in the more recent formations. 
* ‘Zoology of the Voyage of H. M.S. Samarang,’ p. 19. 
