230 
TABLES OF FOSSILS 
Table II.— continued. 
1 
Coralline Crag. 
Walton Crag. 
Norwich Crag. 
Chillesford Crag. 
Weybourn Crag. 
<D 
rO 
o 
u 
Valvata piscinalis, Mull, ... 
X 
X 
X 
Vertigo antivertigo, Drap. 
X 
Vitrina pellucida, Miill. - » - 
X 
Zua subcylindrica, Linn. - 
X 
X 
Bulimus lubricus, 
Miill. 
Zonites, sp. - 
X 
Lamellibranchiata. 
Aiiodonta cygnea, Linn. - 
X 
X 
Corbicula fluminalis, Miill. 
X 
X 
X 
X 
X 
X 
Extinct ill Britain. 
Cyclas, see Sphaerium. 
Pisidium amnicum, Miill. 
X 
X 
X 
X 
-astartoides, 
X 
X 
X 
Extinct. 
--casertanum, Poli 
X 
---- henslowianum, Shep. - 
X 
-nitidum, Jenyns 
X 
-pulchellum, Jenyns 
X 
-pusillum, Gmel. 
X 
-roseum, Scholtz 
X 
Sphserium corneum, Linn. 
X 
X 
X 
-ovale, Fir, 
X 
--—. rivicola, Leach 
X 
Unio littoralis, Lam. - 
? 
Forest-bed (A. Bell), 
Southern. 
»—« pictorum, Linn. 
? 
X 
X 
JPisidium astartoides has generally been considered to be a variety of 
P. amnicum, though at West Runton the two species are found side by side 
with the valves united, and among several hundred specimens of each no 
intermediate forms could be found. At present there is no agreement 
among conchologists as to the limits of the different species in the genus 
Pisidium, but nearly all the British forms seem to occur in the sandy 
portion of the bed at West Runton. 
Figures of many of the Pliocene land and freshwater mollusca will be 
found in Plate Y. of this work; in S. Y. Wood’s “Crag Mollusca ” ; and 
in Sandberger’s “ Ein Beitrag zur Kenntniss der unterpleistocanen 
Schichten Englands,” Pal(jeontogra]phica, 1880. 
