2gO BUTTERELL : THE MOLLUSCA OF BEVERLEY. 



ft, in. 



Brown Warp - - - - 4 6 



Black do. - - - -10 



Brown Clay - - - -30 



Do. Silty Warp - - -16 



Dark Warp 8 6 



Black Soft Warp - - - - 9 3 

 Black Wick Sand full of water - 13 3 

 Black Sandy Warp - - - 2 6 

 Gravel- - - - - -10 



44 6 

 Marl below this and then probably the Chalk. Bands of 

 Peat occur, and amongst the Silty Warp in sub-fossil form are to 

 be obtained specimens of Afya, Utricuhis^ Cardium, Tellina^ 

 Hydrobia and other estuarine shells, together with several species 

 of Foraminifera; some are covered with serpulte, and the epidermis 

 of Mya is in some cases well preserved. 



It will be observed that some usually common species are 

 not yet recorded, and that the genera Uiiio, Dreissena, Paludiiia, 

 Baha and Acme are entirely absent from the list. 



AaUATIC. 



Sphaerium corneum Lin. Very abundant in nearly every 

 pond, ditch and stream in the district, Figham, 

 Long Lane, Swinemoor, River Hull, Beverley and 

 Barmston Drain. This species is, I believe, most active 

 at night time, and together with Bythinia tentaculata 

 forms a favourite food of the Barbel. 



S. corneum var. flavescens Macgill. Specimens of a pale 

 yellow colour resembling this form occur in the Beverley 

 and Barmston Drain at Figham; this variety appears to 

 prefer streams with a sandy or gravelly bottom. 



S. lacustre Mull. Local and not plentiful: small in size at 

 Figham, in a ditch bordering the Hull Road, also in a 

 ditch running into the River Hull at Commonbank 

 Nook near Arram. 



J.C, iii., April, 1882 



