NELSON AND TAYLOR : ON YORKSHIRE MOLLUSCA. 67 



in 1778, records this species on the authority of Mr. Wallace, 

 under the name of Turbo adversus, as common in the small 

 rivulets in the Orkneys. 



It has been recorded from several localities in North 

 America by G. B. Sowerby, Michaud, and others, but its occur- 

 rence in these regions has not been confirmed by recent observers. 



This species is staled by Mortillet to be Risso's Z. labrosa, 

 but the specimens are now missing from that collection. 



Dr. Martin Lister, in 1678, was the first to record this 

 species for our county. 



2. Lune and Ribble — Abundant amongst Anacharis, pond, Gisburn-in- 



Craven, April i8lh, 1881, W.D.R. ! 



3. Vale of York — Decidedly less common than P. hypnomm about York. 



Unusually fine in the Foss, near Huntington, Rev. \Y. C. Hey, 

 also found at Askham, Bishopthorpe, and many other places, R. 

 M. Christy, 'Zoo!.,' p. 183, 1881 ; found plentifully in the stream 

 south of Heyworth, near York, and frequent elsewhere in still 

 waters (Dr. Martin Lister, 1678) ; in the reedy ditch-expansion lay 

 the left bank of the Foss above Yearsley Bridge, 1858 ! and ditch 

 near the Ouse below York, 1866, \Y. Whitwell ! ditches on 

 Middlethorpe Ings, near ^'ork, 1865, R. Whitwel! ; common at 

 Askham Bog, June 2nd, 1879, W.D.R. ! Boston Spa, toleral)Iy 

 common, J. Emmet, 1882 ; Bishopdyke, at Barkston ! and at Sher- 

 burn, April, 1879 ! Malton, Sept. 23id, 1880, J.D.B. ; pond near 

 Church Fenton Station ! grassy pond, Towton Battle Field ! pond 

 at Scarcroft, June 14th, 1884, W.D.R. ! Tadcaster, 1877, II. C. ! 

 Pond, Riccall, June, 1879! Old Crimple near Spoflbrth, rather 

 common, 29th .Sep., 1889 ! 



4. Number — Goole district, R. D. Maxwell, 1876; in the drains about 



Caslleford and Fairburn, June 15th, 1885, amongst Canadian weed, 

 some very much ridged in the line of growth, and large, G. Roberts ; 

 stream. Ermine Street, Castleford, formerly abundant, now scarce; 

 pond near Fryston Church, April 2nd, 1877 ! Ferry Fryston ! 

 Fairburn, W. H. Broadhead, 1870; Newthorpe, Feb. 12th, 1882! 

 canal near Selby, June, 1879; Burton Hall, Oct. 17th, 1880! 

 abundant in ditch alongside Selby cut, August, 1875 ! Ileming- 

 borough ! ditch near Bond's Ings, South Milford, 1879 ! pond near 

 Ilowden Station ! ditch, Barlow Common,' August, 1881 ! Carlton 

 pond, near Snailh, June 17th, 1882 ! 



5. Hatfield and T/jo/ne— West Moor Drain, Hatfield Chacc, a few, 21st 

 Sep., 1S87, W.D.R.! Thome Waste, Mny 30th, 1888 (Nat. Hist. 

 Journ., Oct. 15th, 1888. xii, 158). 



