THE NON-MARINE MOLLUSCA OF THE WALTON CRAG. 217
2. Hygromia incarnata. (Müll.)
Helix incarnata, R. Bell: "Land Shells in the Red Crag." Geol.
Mag., 1884, vol. i., p. 262.
The unique example of this species from the Walton Crag
is now in the British Museum (Natural History), and was
obtained in 1882 by the late Mr. Groom (alias Groom-Napier,
the soi-disant "Prince of Mantua"). It is by no means a perfect
example, but no doubt can be entertained of the determination.
On the Continent the only fossil record of this species is from
the middle Pleistocene of Cannstadt.
3. Helicodonta lens. (Fer.)
Helix lens, Fer.; R. Bell, op. cit., p. 262.
A single example of this species is stated by Mr. Bell to
have been found at Walton by Mr. Larcher, of King's College,
in 1881, and to have been identified by Dr. J. Gwyn Jeffreys
and Mr. J. H. Ponsonby, but we have failed to trace the
specimen. It is quite unknown in a fossil state on the Continent.
4. Helix lactea. (Müll.)
A fine example of this species is in the Robert Bell Collec-
tion in the British Museum (National History), and is without
doubt the specimen found in 1883 at Walton by Mr. Bell, and
recorded by him in the following year." A fragment of another
example is said to have been found at the same time, but this we
have failed to trace. This form is unrecorded in a fossil state
on the Continent.
5. Paludestrina stagnalis. (Bast.)
Paludestrina ulvae, Penn.: S. V. Wood, Crag Moll., vol. i., p. 109, and
Suppt. i., p. 71, pl. iv., fig. 23, as Hydrobia ulvae ; Hydrobia ulvae,
Penn. : J. Gwyn Jeffreys, Quart. Jour. Geol. Soc., vol. xxvii. (1871),
p. 490.
This species is recorded from Walton by Mr. A. Bell. We
have not seen any examples, but there is no inherent impossi-
bility in the record, since it occurs in the Lower Pliocene
(Congeria) Beds) at Mauer, near Vienna, and Bizenz, in Moravia.
6. Paludestrina ventrosa. (Mont.)
Paludestrina subumbilicata, Mont. : S. V. Wood, Crag Moll., vol. i..
p. 108, pl. xi., fig. 2; Hydrobia ventrosa, Mont.: J. Gwynn
Jeffreys, Quart. Jour. Geol. Soc., vol. xxvii. (1871), p. 490.
2 R. Bell.—"Land Shells In the Red Crag." Geol. Mag., 1884, p. 264.