NELSON AND TAYLOR : ON YORKSHIRE MOLLUSCA. 79 



II. Pollard! stream, Bishopwood, July 31st, 1864! Clifford, August 

 8th, 1871, S. Scholefield ! Malton, September 23rd, 1880, J. D. 

 Butterell! Garforth, 1881, H. Pollard ! 



4. Number — Stream near park, Pontefract ! stream near church, Water 



Fryston ! Selby Cut and neighbouring ditch, June, 1879 ! ditch, 

 Birkin, October 17th, 1880! near Bar House, Ermine Street, 

 Castleford ! ditch, Brayton, October 17th, 1880! Ledstone ! pond, 

 Camblesforth, August, 1881 ! ditch and pond, Carlton Park, Snaith, 

 W.D.R. ! ditch, Burton Salmon! canal, near Burton Hall, Oct. 

 17th, 1880 ! Barlow, near Selby ! South Milford, November 12th, 

 1882! old lime canal, Brotherton, February 5th, 1882! ditch and 

 Stocking Drain, near Hillam ! ditch near Lumby ! Wressel Castle ! 

 numerous in old channel of River Ouse at Hemingbrough, 28 June, 

 1890! and near railway, Hagg Lane, Hemingbrough, 28 June, 1890! 



5. Hatfield and Jhorne — Common in ditch parallel with Black Bank 



Drain, April I4lh, 1883, W.D.R. ! common in ditches, Ackholme. 

 May 14th, 1883, W.D.R. ! Kirk Sandall and Barnby Dun, July 2nd, 

 1886. G. Rolierts ! abundant in Huggin Drain and West Moor 

 Drain, near Hatfield, Sept. 21st, 18S7, W.D.R. ! 



6. Trent — Conisborough. June 2nd, 1873. J. Wilcock ! ponds, Doncaster, 



J. Hardy ! Anston Crags, April 30lh, 1885, W.D.R. ! plentiful in 

 Chesterfitld Canal, near Kiveton Park Station, April 30th, 1885, 

 W.D.R. ! 



7. Wer)t Vale — Common alwut Ackworlh, C. Ashford, Zool., 1854, 



p. 4263 ; ditch, Hessle, near Ackworth, March 19, 1882 ! pond, 

 near plantation, Ackworth, March, 1S83, and ditch, Grosvenor 

 Place, Ackworth, March, 1883, H. Richardson ! pond at Nor- 

 ton, April 22, 1878 ! VVentljridge, G. F. Linney, 1880, J. Whit- 

 wham ! river Went at Norton, April 22, 1878 ! and at Ladythorp, 

 J. Whitwham ! .Smeaton Crags, in ditch by side of river Went ! 

 Cross IJill, near Pollinglon, April, 1882! Moss, near Askern, April, 

 1882 ! stream near Askern pool ! Hemsworth dam, Jan. 16, 1882 ! 

 (H. Richardson, Nat. Hist. Journ., 1882, vi., p. 73); common in 

 pond and in ditches, Cowick Park and in West Cowick brick-pond, 

 June 17, 1882, W.D.R. ! Whit Hall, near Doncaster, J. Whitwham ! 

 Campsall, May 20, 1886, S. II. Bennett ! Birka drain, Womerslcy, 

 H. Crowther ! near Sharlston Hall ! 



8. Dearne — Dearne and Dove Canal, June 30th, 1884, W. E. Brady ! 



Wakefield and Barnsley Canal, near Barnsley, March 29th, 1878 ! 

 near Barugh Lock, A. P. Taylor ! and at Royston, March 29th, 

 1868! common in fish jxind, Cusworth Park, near Doncaster, May, 

 1885, T. II. Easterfield ! Cawthorne, J. Whitwham! a])undant in 

 canal, Stairfoot, 1884, J. Gelderl Denby Dale! 



9. Don — A few in a field-drain leading into Cubley Brook, Pcnistone, 



.September 1889, L. E. Adams! Common in Mill dams, Riveliri 

 Valley, June 2nd, 1881. W.D.R. ! 



