204 Mrs. McKenny Hughes—Pleistocene Mollusca. 
sham and. Reculvers, and by Prof. Prestwich! from Summertown 
near Oxford. It also occurs in the gravels of the basin of the Cam 
and Ouse. It occurs in Belgium and in France in the ancient 
alluvium of the Seine and Somme. ‘This therefore appears to be a 
southern shell, which had formerly a more northern range. 
The six following shells are extinct in Britain, but most of them 
have a wide range in Europe and Asia :— 
Unio litoralis, Lamk., is, according to Moquin Tandon,? found in 
almost all the rivers of France. Kobelt records it also from Spain, 
Morocco, and Algeria. 
Unio pictorum, var. limosa, Nils., according to Moquin Tandon, 
occurs in almost all the rivers and brooks of Northern France. 
Hydrobia marginata, Mich., lives in France, says the same author, 
on dead leaves under water and on aquatic plants at Var, Vaucluse, 
L’ Aveyron, the Haute Garonne and the Jura. 
Helix (Frutieicola) fruticum, Mill., is found all over Turope with 
the one exception of England. It ranges as far north as St. Peters- 
burg.’ Moquin Tandon‘ says that it is found over almost all northern 
and central France, but that it does not occur in the southern part. 
Miss Esmark records it from North and South Norway, Sweden, 
and Finland. She says, “It is not very common, but plentiful where 
it occurs.”° Iam told by Mr. Cooke that it occurs also in North- 
West and East Siberia and the Altai Baikal district. 
Patula ruderata, Studer, has a very wide range. Kobelt records 
it from the Caucasus, Europe, Northern Africa, and the whole of 
Western Asia. Jeffreys from Kamschatka, South Russia and Austria, 
and North Japan.® Clessin says that it lives in the mountainous 
parts of Germany and in the Alps. Moquin Tandon says it is found 
under stones and dead leaves in the Jura. Miss Esmark records it 
from Norway, Sweden, and Finland, and remarks that it is “one of 
our most common species, which goes as well to the far north as on 
our highest mountains, wherever it is possible for any Molluscs to 
live.’*? Mr. Cooke informs me that it is found also in West and 
Hast Siberia, Amurland, North China, Japan ? and North Persia. 
Clausilia pumila, Ziegler, is, according to Clessin,® distributed over 
a great part of Germany, but is most common in the North. Its 
range is eastward to the Siebenbtirgen; southward to Croatia ; 
northward to Livland and Sweden; it finds its western limit in 
Germany, and does not occur in England except as a fossil. 
It has hitherto been recorded from the gravels of Cambridge as 
C. biplicata, but Mr. B. B. Woodward® has shown that all the 
shells referred to that species are really the C. pumila of Ziegler. 
1 Grou. Mac. n.s. Vol. IX. 1882, p. 49. 2 Hist. Nat. des Mollusques. 
> Clessin, Deutsche. Excurs. Mollusken-Fauna, p. 166. 
4 Op. cit. vol. il. p. 198. 5 Esmark, Journ, Conch. vol. v. pp. 106, 126. 
6 Jeff. Brit. Conch, vol. v. Supplement, p. 158. 
7 Journ. Conch, vol. v. p. 104. 8 Op. cit. p. 312. 
9 Since this paper was sent to press a valuable communication has been made by 
Mr. Woodward to the Geol. Assoc. (March 2, 1888) on the shells of the Barnwell 
Gravel, founded chiefly on Mr. Dewick’s Collection. Spheriwm lacustre has been 
inserted above on his authority. 
