SOPPITT AND CARTER : UPPER AIREDALE MOLLUSCA. 



95 



VALVATIDAL. 



Valvata piscinalis Mlill. Generally distributed in the Leeds and 

 Liverpool Canal ; Bingley, not uncommon, Saltaire, and Thackley, 

 occasionally. A few specimens at Malham Tarn approaching 

 var. acuminata, 1883 (Roebuck and Butterell). Dead specimens 

 in abundance on the margin of the Tarn, 1887. 

 Var. subcylindrica Jeff. Canal, Bingley. 



LIMN^ID^. 



Planorbis nitidus Mlill. Extremely abundant in Frizinghall 



Dam, near Bradford. Occasional in canal, Saltaii'e, Apperley ; 



and ditch, Dowley Gap, near Bingley. 

 Planorbis nautileus L. One specimen, Malham Tarn, 1883 



(Roebuck and Butterell). Canal, Saltaire and Bingley 



(J. Wilcock, in Trans. Y. N. U.). 

 Var. crista L. Abundant in mill-dam at Tong Park, 1887. 

 Planorbis albus Miill. Generally distributed and common. 



Frizinghall Dam ; Beckfoot Lane ; canal, Bingley to Calverley ; 



pond, near Bingley old river-bed, Keighley ; mill-dam, Tong 



Park. Skipton (W. Nelson). 

 Var. draparnaldi Shepp. Dam at Thackley ; canal, Bingley. 

 Planorbis spirorbis Mlill. Locally abundant. Ditches at 



Thackley ; Dowley Gap, near Bingley ; and Airton. 

 MoNST. scalaris. A single specimen in a ditch at Dowley 



Gap, near Bingley, Jan. 22nd, 1887. 

 Planorbis vortex L. Common in canal near Bingley; rare, 



Saltaire ; Calverley, 1872 (H. Shaw). 

 Planorbis carinatus Miill. Generally distributed and common. 



Abundant in pond on Baildon Green; pond at Tong Park; 



canal, Bingley to Calverley. 

 Planorbis complanatus L. Extremely rare. Canal, Calverley 



1872 (H. Shaw). Not found since. Perhaps a case of mistaken 



identity. 



Planorbis COrneus L. Not a common species. Frizinghall 

 Dam ; pond on Baildon Green, introduced twenty years ago by 

 Mr. T. Hey ; pond at Fagley ; ditch, Steeton (J. Ellison). 



Planorbis contortus L. Abundant and generally distributed. 

 Canal, Saltaire, Bingley; ditches, Dowley Gap, and near 

 Cottingley Bridge ; abundant, Malham Tarn. 



Physa hypnorum L. Extremely local, having only been met 

 with by Mr. W. E. Collinge, M.C.S., of Leeds, who informs us 

 that he found it in profusion at Bell Busk. 



April 1888. 



