( 51 ) 
a Helis, Lam. Globulous, pl. 7, fig. 9. 
6 Garacolla, Lam. Carinated, conical, pl. 7, og. 22 
c Anostoma, Lam. Mouth dorsal, toothed, pl. 7, fig. 20. 
18. Heuicrna. (1) Lam. 
Subglobulous or coni- Columella callous. Terrestrial. 
cal; spire a little depress- VY. Animal, p. 66. 
ed; inner lip enlarged at 
the base in a callous pad 
entirely covering the um- 
bilicus ; a small blunt an- 
le at the base of the right 
ip. Pl. 12, fig 6. 
49. Hexicarton. Ferruss. 
Very thin, transparent. Columellaspiral, solid, © Marine. 
formed by the inner lip —_ Australasia. 
and confounded withthe Y. Animal, p. 62. 
whorl of the mouth. 
20. Amputrarta. (2) Lam. 
Round and yentricose, | Columella umbilical. 
spire short; umbilicate ; i 
operculum horny. 
as 
Mouth narrower, Inner lip sharp. Fresh VWVaters of warm 
more elliptical, thinner. climates, 
BE Os ifies 1. 
6, Ampullina. 
Considerably thick- Marine. 
er. P1.9, fig. 2. V. Animal, p. S/, 
method of distribution, impressing that it is purely artificial. The Helices being 
terrestrial shells, it appears extraordinary that we should meet with them in the 
fossil state in marine deposits; but when that happens they have been brought 
there by floods or rivers, or by some irruption of the sea, attesting that previously 
to these deposits there had been dry land in the same places, whereon the animals 
lived which formed the shells. The Marl Pit of Touraine is the only place on 
record where they thus occur, and there they are frequeutly filled with the remains 
of Polypi and marine shells. Fossil Helices are generally found in Fresh Water 
Formations, and often accompanied by Lymnzi and Planorbes. We meet with 
them in breccia, and sometimes in the districts which have been overthrown by 
volcanoes. In England they have been found in the Cowes Rock of Limestone, in 
the Green Sand, and in the Derbyshire Peak Limestone. 
(1) Foss. Blue Lias Limestone. 
(2) Their opercula, being horny, are never found, although these shells are very 
common in beds of coarse, calcareous, shelly matter ; whilst the opercula of the 
Natice, to which some authors would refer them, are very frequently met with, 
from their being calcareous. Fossil Ampullariz are also found in the extinct vol- 
canoes of the valley of Ronca, where they have been so disposed by the eruptions 
as to preserve their colours. M. Faujas found a species of Ampullaria, with a very 
thick shell, at St. Paulet, near Pont St. Esprit, in bituminous marl, above a mine of 
fossil coal; the upper edge of each whorl bears an ascending keel, and it differs 
from all that are Con, by an oval mouth, pl, 12, fig 12,13, 14. 
