DERBYSHIRE LAND AND FRESHWATER SHELLS. 10') 



DERBYSHIRE LAND AND FRESHWATER SHELLS. 

 CLASS I., CONCHIFERA. 



FAMILY I., SPH^EIID^. 



GENUS I., SPH.EBIDM. 



Splicerium corueum, very common. 



var. flavescens, canal at Cromford, Bretby. 

 rivicola. Canal at Matlock and Willington. 

 lacustre, vai'. Ryckholtii, Pool near Winstar. 



GKNUS II., PISIDIUM. 



Pisidium amnicum, Canal at Ambergate. 

 fontinale, Stanton in the Peak. 



var. cinerea, Stanton in the Peak. 

 pusilhim, Pools near Winster. 



„ var. obtusalis, Pools near Winster. 

 nitidum, Via Gellia. 



FAMILY II., UNIONID^. 



GENUS I., UXIO. 



Unio tumidus, Canals at Cromford and Willington. 

 var. radiata. Park Pond, Repton. 

 var. ovalis, ,, ,, 



pictorum, Cromford Canal, Park Pond, Repton. 



GENUS II., ANODONTA. 



Anodonta cygnea, common. 



var. Zellensis, Park Pond, Repton. 

 anatina, ,, ,, 



var. ventricosa, ,, ., 



var. complauata, ,, ,, 



FAMILY III., DREISSENIDiE. 



GENUS I., DKEISSENA. 



Dreissena polymoi-pha. Canal at Willington. 



CLASS IL. GASTEROPODA. 



ORDER I., PECTINIBRANCHIATA. 



FAMILY I., NERITID^. 



GENUS 1., NEKITINA. 



Neritina fluviatilis, Canal, Willington. 



FAMILY II., PALUDINIDiE. 



GENUS I., PAIjUDINA. 



Paludina vivipara, common. 



GENUS II., BYTHINIA. 



Bythinia tentaculata, common. 



var. decoUata, Cromford. 

 Leachii, Eggington. 



FAMILY III., VALVATID^. 



GENUS I., VALVATA. 



Valvata piscinalis, common. 



ORDER II., PULMONOBRANCHIATA. 

 F.OIILY I., LIMN^ID.E. 



GENUS I., PLANORBIS. 



Planorbis albns, Pond at Milton. 

 giaber. Pits near Willington. 



