194 



JOURNAL OF CONCHOLOGY, VOL. l6, NO. 6, JUNE, I92I. 



Name of Species. 



Records in italics require 

 conriimation. 



Severn. 



ENGLAND AND WALES 

 South Wales. 



w ^ 



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eO'^>o<Di>>ooojo 



o m 



O a, CJ 



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North Wales. 



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B. leachii 



Viviparidse 

 Paludina contecta 

 P. vivipara 



Valvatidse 

 Valvata piscinalis 

 V. macrostoma 

 V. cristata 



Assemaniidse 

 Assemania grayana ... 



Pomatiidae 

 Cyclostoma elegans ... 



Aciculidse 

 Acme lineata 



Nepitidse 

 Neritina fluviatilis ... 



Dreissenidse 

 Dreissena polymorpha 



Unionidae 

 Unio pictorum 

 U. tumidus 



Marg. maigaritifera ... 

 Anodonta cygnea 

 A. anatina 

 Pseudanodonta sp. ... 



Cypenidse 

 Sphgsrium rivicola ... 

 S. corneum 

 S. lacustre 

 S. pallidum 

 Pisidium amnicum ... 

 P. casertanum 

 P. henslowan.um 

 P. hibeniicum 

 P. lilljeborgi 

 P. milium 

 P. nitidum 

 P. obtusale 

 P. parvulum 

 P. personatum 

 P. pulchellum 

 P. subtruncatum 

 P. supinum 

 P. tenuilineatum 



Total species 163 



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