DIVISION XII. 
4. PATELLA. (1) Lin. 
Oval or almost orbicular, 
in dilated cones, more or 
less obtuse and concave 
beneath. PI. 5, fig. 5,6. 
2. Fissunetra. (2) Lam. 
3. Emareinuta. (3) Lam. 
4. Scutus. Montf. Par- 
MAPHORA. Blainv. 
Elongated, flattened ; 
summit apparent towards 
the posterior part, which 
is rounded; the anterior 
truncated. PI. 5, fig. 4. 
5.  Seprarra. 
NAVICELLA. 
Feruss. 
Lam. 
Summit symmetrical , 
inclined towards the pos- 
terior edge : an opercu- 
lum. PI. 5. fig. 23. 
6 AncyLus. Geoff: 
Conical. 
a. PI.5, fig. 7. 
(24) 
GENERA. 
~ 
A small hole at tke 
summit. Pl. 5, fig. 10. 
A notch at the poste- 
rior edge. Pl. 5, fig. 11. 
A horizontal plate 
within. 
6. Plectrophorus, Fer. With an interior winding 
impression. PI]. 6, fig. 2,3. 
CLYPEACE/. 
Mostly marine, ad- 
hering to the rocks and 
other hard substances 
bordering the sea. 
VY. Animal, p. 73. 
Marine. VY. Animal, 
p- 72: 
- 
Marine. VY. Animal, 
p.. 72: 
Marine. New Zea- 
land. Fossil species at 
Grignon.. Animal un- 
known. 
In the rivers of warm 
climates. 
Y. Animal, p. 72. 
VY. Animal, p. 63, 
Fresh-water. 
Terrestrial. 
Teneriffe. Maldives. 
(1) The animal of the fresh-water Patella differs from that of the marine, 
although the shell has. scarcely any distinguishing character. 
The fossil species 
P. cornucopie (pl. 5. fig. 6.) resembles a cap, and is of considerable thickness. 
Foss. in Alluvia; Crag Marl; Chalk Marl; Clunch Cla 
Forest Marble.—Grignon; Houdan; Pontoise. 
ry; Alum Shale of Whitby ; 
(2) Foss. in the beds of coarse marine limestone at Grignon, and in the marl-pits 
of Touraine. 
. (3) Foss. in Limestone analogous to that at Grignon. 
