GASTEROPODA.. 343 
CARINARIA, Lamarck. 
Fir 141.* 
Etymology, carina, a keel (or keeled vessel). 
Type, C. cymbium, Desh. = C. cristatus, L., Fig. 141, Pl. 
Pen... Bie. 19. 
Shell hyaline, symmetrical, limpet-shaped, with a posterior 
sub-spiral apex and a fimbriated dorsal keel: nucleus minute, 
dextrally spiral. 
Animal large, translucent, granulated; head thick, cylin- 
drical; lingual ribbon triangular, teeth increasing rapidly in 
size, from the front backwards ; tentacles long and slender, eyes 
near their base; ventral fin rounded, broadly attached, with a 
small marginal sucker ; tail large, laterally compressed ; nucleus 
pedunculated, covered by the shell, gills numerous, pinnate, 
projecting from beneath the shell. 
Distribution, 8 species. Mediterranean and warmer parts of 
the Atlantic and Indian Oceans. They feed on small Acalephe, 
and probably on the pteropoda; Mr. Wilton found in the 
stomach of a Carinaria two fragments of quartz rock, weighing 
together nearly 3 grains. 
Fossil, 1 species. Miocene. Turin. 
CARDIAPODA, D’Orbigny. 
Lzample, C. placenta, Pl. XIV., Fig. 20. 
Etymology, cardia, heart, pous, foot. 
Synonym, Carinaroides, Hyd. and Souleyet. 
Animal like Carinaria. 
Distribution, 5 species. Atlantic. 
Shell minute, cartilaginous ; peristome expanded and bi-lobed 
in front, enveloping the spire behind. 
FAMILY II.—ATLANTIDA. 
Animal furnished with a well-developed shell, into which it 
# Fig. 141. p, proboscis; ¢, tentacles; 0, branchie; s, shell; 7, foot; d, disc, 
