IV PREFACE. 



' moderately commou/ ' rare/ etc., must be taken with great cautiou, 

 especially the latter, as subject to contiDual chauge. 



A list is given of British Fossil Shells identical with now living 

 species. 



A familiar description of British Mollusca and some peculiarities in 

 their families and genera will, it is hoped, form a useful and suitable 

 introduction to the names and figures. The Author's best thanks are 

 due to his friends, Madame De Burgh, who has collected many beau- 

 tiful shells; R. M'Andrew, Esq., F.L.S., whose dredging experiences 

 are so extensive ; J. G. Jeffreys, Esq., F.E.S., etc., whose researches 

 have resulted in so many additions to our Fauna ; Mr. Brice Wright, 

 the Naturalist, of Great Eusseil Street, and others, who have in the most 

 liberal manner supplied him with specimens from wjiich his drawings 

 are taken. The loan of delicate and minute shells to authors and artists 

 has so often proved disastrous, that nothing but a generous friendship, 

 and a zealous love of Natural History, could have induced proprietors 

 so freely to incur the risk. 



