EARTH 



SCIENCES 



LIBRARY 



PREFACE TO THE REPRINT. 



Although I have for some time contemplated a revision of this bulle- 

 tin, for which I have accumulated much material, the pressure of other 

 work has prevented this plan from being carried out. Meanwhile the 

 usefulness of the hook as a handy illustrated catalogue has resulted in 

 the complete exhaustion of the original edition, and the reprinting of 

 it from the stereotype plates became necessary. Doctor Agassiz most 

 courteously lent the original drawings of Plates X to XXXVI, which, 

 in the edition of 1889, were printed from the lithographic stones pre- 

 pared for the Blake Report and which are in that form no longer avail- 

 able. To increase the usefulness of the work 21 additional plates from 

 the Proceedings of the United States National Museum, published 

 since 1889, have been added to the 74 originally contained in this bul- 

 letin, making a total of 95 plates, containing about 1,192 figures of 770 

 species. The defects of a hastily compiled catalogue and the defi- 

 ciencies due to lapse of time and the progress of science, although not 

 to be ignored, it is hoped will be outweighed by the convenience for 

 collectors of a systematic list so abundantly illustrated and to which 

 is added the very considerable amount of information as to distribution 

 in latitude, range in depth and time, etc., which are included in com- 

 pact form in the tables. 



The reader should note that no change whatever has been made in 

 the text, except the addition of (1 ) this preface; (2) of explanations to 

 the new plates, and (3) a supplementary index of the species repre- 

 sented on the newly added plates, some of which do not occur in the 

 tables. 



The author will be gratified to receive from any source data or mate- 

 rial useful for correcting or amplifying this list in the still projected 

 future revision. 



WILLIAM HEALKY DALL. 



WASHINGTON, D. <_)., February, 1903. 



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