PLATE CVI. 



This Shell, we observed in plenty, on the sandy shores of South 

 Wales, and particularly on those of Pembrokeshire. It is also found 

 on the western coasts ; at Highlake in Cheshire, near Liverpool ; at 

 the mouth of the river Mersey ; and on the coast of Aberdeenshire 

 and other shores of Scotland. 



The general colour of the outside is a kind of milky white, deli- 

 cately radiated with brown ; within, the young shells are tinged with 

 reddish brown, the old ones with violet. 



