KENNAED & WOODWAED : BRITISH PLIOCEITE NON-MARINE MOLLUSCA. 201 



120 metres. V. tnedia is considered by Sandberger to be related to 

 V. laeta, Martens, from Japan. ^ We cannot agree with Frauenfeld 

 that this species is identical with P. unicolor, Oliv, the latter having 

 a much more pointed apex and rounded month ; whilst the whorls 

 are more scalariform than in V. media, and slightly carinate. 



32. Yalvata cristata, Miill. 



Valvata cristata, Miill. : S. Y. Wood, Crag Moll., Suppt. II, p. 36, 

 pi. iv, fig. 8. 



Form. andLoc. — N'orwich Crag : Bramerton Common (Norwich Mus.). 



No further examples of this species have been found since it was 

 first noticed by Wood. The lower pleistocene of Mosbach is the 

 earliest record for this form on the continent, though it is noted from 

 several localities of more recent age. 



33. Yalvata piscinalis (Miill.). 



Valoata piscinalis, Miill. : S. Y. Wood, Crag Moll., vol. i, p. 112, 

 pi. xii, fig. 3. 



Form, and Loc. — Norwich Crag : Bramerton Common and Blake's 

 Pit, Bi'amerton (Norwich and Brit. Mus.). 



All the examples we have seen of this species are typical, the 

 " var. antiqua " being unknown. It has also been found in the 

 lower pliocene (Congeria Beds) at Moosbrunn, near Yienna, and 

 St. Leonhards, in West ISlavonia. 



34. CoRBICULA ELTJMINAIIS (Miill.). 



Cyrena trigonula, S. Y. Wood: Lyell, Mag. 'Nat. Hist., 1839, ser. ii, 



vol. iii, p. 329. 

 Cyrena consolrina, Caill. : S. Y. Wood, Crag Moll., vol. ii, p. 104, 



pi. xi, fig. 15. 

 Corhicula fluminalis, Miill. : S. Y. Wood, Crag Moll., Suppt. I, p. 119. 



Form and Loc. — Red Crag: Waldringfield (A. Bell). Norwich 

 Crag : Belaugh ; Aldeby ; Dunwich ; Yarn Hill ; Thorpe, Aldeburgh ; 

 Bulchamp ; Bramerton; Postwick ; Wangford (S, Y. Wood). 



It is indeed remarkable how enormous has been the decrease in 

 the area of distribution of this species since pleistocene times. In this 

 country it occurs in beds of every age from the Red Crag to the 

 upper pleistocene. It is first noted on the continent from the upper 

 pliocene of Bligny, near Dijon, France, and it occurs abundantly in 

 pleistocene deposits of that country, as well as in those of Belgium, 

 Germany, and Austria, whilst it has been met with in similar beds as 

 far east as Omsk, in Siberia. In modern clays it is confined to Asia 

 Minor, the Euphrates, the Nile, South Africa, and Kashmir. 



1 C. L. F. Sandberger, " Beitrag zur Keuutniss der imterpleistocauen Schicliten 

 Englands ' ' : Palajontograpliica, 1881. 



