W. D. ROEBUCK : LINCOLNSHIRE MOLLUSCA. 



265 



Ditch alongside Black Bank Drain, common, April 14th, 1883 ! (W.D.R.)- 

 Sutton, a few! (II. W. Kew, April 1887). Welton Vale, near Louth, dead ! 

 (H. W. Kew, 13, V, 87). Benniworth Haven, near Louth, two ! (H, W. 

 Kew, 7, vi, 87). 



South Lincolnshire. — Rejectamenta from between Bracebridge and Lincoln, 

 December 1884! (C. T. Musson). Near Boston, one, September 8th, 1884 ! 

 (W.D.R.). 



Planorbis lineatus Walk. 

 Has been found in one locality. 



IJorth Lincolnshire. — Grainthorpe, near Louth ! (Miss Longley, per II. W. Kew, 

 16, iv, 87). 



Planorbis nitidus (Miill.). 

 Has been recorded for a locality in each division of the county. 



l^orth Lincolnshire. — A drain at Brigg (T. Ball, Science Gossip, 17, iv, 1866)— 

 not seen. 



South Lincolnshire. — Rejectamenta from between Bracebridge and Lincoln, 

 December 1884 ! (C. T. Musson). 



Planorbis nitidus var. albida Nels. 



North Lincolnshire. — Took about a dozen pure milk-white specimens with many 

 of typical colour in a drain at Brigg (T. Ball, Science Gossip, 17, iv, 1866) — 

 not seen. 



Planorbis nautileus (L.). 



Numerous in a few localities in the vicinity of Alford and Louth. 

 Not recorded for any other district. 



North Lincolnshire — Pond, Ailby, near Alford, numerous amongst Leuinatrisiilca, 

 April 14th, 1886 (W.D.R. ). Pools at land-foot of sandhills, Sutton-in-the- 

 Marsh, numerous, April 1 6th, 1886 (W.D.R.). Pond at Raithby, near 

 Louth ! (H. W. Kew, 7, vi, 87). Pond in post-glacial valley by Haugham 

 Wood, Louth, a few ! (Id.). 



Planorbis albus Miill. 



Recorded in the North for Wroot, Louth, and Alford districts, 



and in the South for the vicinities of Lincoln and Crowland. 



North Lincolnshire. — Canal near Louth, numerous on caddis-cases, and in the 

 debris on the bank, April 15th, 1886! (W.D.R. and H. W. Kew). Rejecta- 

 menta of Main Drain, Chapel, one, August 20th, 1886! (J. E. Mason). 

 On caddisworm cases, Black Bank Drain, Candy Hall Bridge, April 14th, 

 1883; (W.D.R.). 



South Lincolnshire. — Rejectamenta from between Bracebridge and Lincoln, 

 December 1884 ! (C. T. Musson). Crowland Wash, July 1886 ! (T. W. Bell). 



Planorbis spirorbis Miill. 

 Found in a few places near Louth, Alford, and Sutton, and in 

 the Southern division near Boston. 



North Lincolnshire. — Louth Canal, a few, April 15th, 1886! (W.D.R. and 

 H. W. Kew). Sutton-in-the-Marsh, a few in the coast drains, with vortex^ 

 April i6th, 1886! (W.D.R.) Rejectamenta of Main Drain, Chapel, August 

 20th, 1886, a few! (J. E. Mason). Greenfield Wood, Ailby parish, two, 

 June 8th, 1887! (J. E. Mason). 



South Lincolnshire.— Near Boston, one, September 8th, 1884! (W.D.R.). 



Sept. 1887. 



