OF SOUTHERN INDIA. 325 
limestone by Phillips. Hall also refers a few silurian species from America to the 
same genus, and Eichwald (Leth. Ross., Vol. I, 1860, p. 1098) describes several 
palzeozoic species some of which, like Met. solare (non id. Koninck), are covered 
with radiating ribs. 
Except the remarkable Capulus Troscheli, Miller, from the Senonien deposits 
of Aachen, I am not acquainted with any cretaceous species which would particu- 
larly resemble the paleeozoic Metoptome. 
XLVI. Family,—_LEPETIDZ. 
Gray, Guide, 1857, p. 172; H. and A. Adams, Gen. I, p. 462. 
This small family includes only a few species which H. and A. Adams noted 
under the genus Lepeta and the sub-genus Jothia in the family Tecrvrmz. The 
lingual riband has one central tooth, like that in the Caputip2, but only two lateral 
teeth on each side instead of three, and all of them are of a somewhat different 
shape. The animal otherwise resembles that of the Tzcruvri#, but according to Gray 
many of the species are not known to possess eyes, and the gills are said to be 
often rudimentary, although Forbes and Hanley (Brit. Shells, Vol. IT, p. 443) speak 
of a branchial plume (two plumes ?) being cervical. Judging from the great depth 
out of which Lep. ceca, Miller (Propilidium ancyloide, Forbes) is generally dredged 
alive, we may suppose that gills can scarcely be wanting. 
The shell of the Lzprrm* resembles that of some Capvzipz with subspiral 
apex. From Helcion it is distinguishable by the horse-shoe-shaped muscular 
impression in the interior of the shell. This last character shows that the family is 
closely allied to the Capuzrps. 
Gray quotes in it two genera, Lepeta, Gray, and Lothia, Forbes. Of the 
first, according to H. and A. Adams, there are four,* and of the latter only one 
living species known. The fossil ones can only with great difficulty be distinguished 
from Capulus, Cochlolepas, Helcion, Tectwra and others, unless the thin shell is 
perfectly well preserved. 
We only know a small number of cretaceous shells which strongly recall the 
characters of some of the recent Lzpzrm#, and which have been named by Meek 
and Hayden Anisomyont (Am. Jour. Se. and Arts, 1860, XXIX, p. 35). The 
species attributed to this genus are principally distinguished from Patella and 
Cochlolepas by their thin shells; the apex is curved backward as in Lepeta, but not 
spiral as in Capulus; the internal muscular impression is horse-shoe-shaped and 
is interrupted in front as in Lepeta. The exterior surface of the shell is gene- 
rally smooth, with distinct lines of growth, but not often with radiating strie. 
* Lovén proposed (vide Vetensk. Akad. Forhandl., 1859, p. 119) for the Pilidiwn commodum, Midd., the 
name Piliscus, and describes another species P. probus; both ought to be placed in the Vezurivipz, The 
determination of the species as well as that of the genera is in fact rather uncertain. 
+ Some of the species of Anisomyon exhibit a great relation to species of the paleozoic Cyrtolites, like 
C. ? expansus, Hall, (Pal. New York, III, p. 479, pl. 114, figs. 4-5). 
4 L 
