PREFACE. 
As the present short Monograph completes my work on British Fossil Cirripedes, 
I beg to be permitted again to have the satisfaction of returning my very sincere thanks to 
the many naturalists who have placed their collections at my disposal, and have given 
me the freest permission to use the specimens, in whatever manner | might find necessary, 
—My thanks are most especially due to Mr. Searles Wood, Mr. Bowerbank, and 
Sir Charles Lyell; and to Mr. J. de C. Sowerby for the use of the original specimens 
figured in the ‘ Mineral Conchology.’ lie, also, under much obligation to Mr. D. Sharpe, 
Mr. Greenough, Mr. Smith of Jordan Hill, Professor Tennant, Mr. Charlsworth, 
Mr. F. Edwards, Dr. 'T. Wright, Professor Forbes, Professor Henslow, M. Bosquet, and to 
many others. I must, also, be permitted to tender my grateful thanks to the Council of 
the Palzeontographical Society for the very hberal manner in which they have allowed my 
two Monographs to be ulustrated. 
