PREFACE. 



Having so lately, in my volumes on the Recent and 

 Fossil Lepadidse, expressed as strongly as I could, and with 

 the utmost sincerity, the obligations under which I lie to 

 very many naturalists, I will not here repeat my thanks, 

 and will only say that the assistance formerly rendered me 

 from so many quarters has been most kindly continued 

 without intermission. The references under the Habitats, 

 in which I may remark the names of Mr. Cuming and of 

 Mr. Stutchbury, and of the British Museum, so often recur, 

 show my deep obligations to these gentlemen and to 

 Dr. Gray, and indeed to most of the British and several 

 Foreign* collectors of recent and fossil shells. At the 

 period when the Introduction to this volume was printed, I 

 stated that I did not know whether the Palaeontographical 

 Society would publish the few British fossil Balanidse ; the 



* I feel under special obligation to Mr. Dana for several very interesting 

 communications connected with the present subject, and for information 

 derived from his magnificent work on the Crustacea, collected during the 

 United States Exploring Expedition. Also to M. Bosquet, of Maestricht, for 

 the loan and gift of several interesting fossils, described and illustrated with the 

 utmost fidelity, in his beautiful " Monographic des Crustaces fossiles du terrain 

 Cretacee du D. de Limbourg." 



