PREFACE. 



r I THIS, the third volume of the Catalogue of the Collection of Books, Maps, &c., 

 in the Natural History branch of the British Museum, brings the series of 

 entries under the authors' names down to the end of the letter "0." 



The lines on which it has been prepared have been fully set forth in the 

 " Introduction " to the first volume. 



The publication of the present volume has been greatly delayed by other library 

 work, including the re-arrangement and re-pressmarking of the books in the General 

 Library. 



Thanks for assistance in its production are due, not only to the persons already 

 mentioned in the Preface and Introduction to the first volume, but also, owing to 

 changes in the staff, to Dr. A. B. KENDLE, Mr. L. J. SPENCER, and Mr. G. C. CRICK, 

 now acting respectively for Botany, Mineralogy, and Geology ; and further, to Dr. KNUD 

 ANDERSEN, who has for some time past given most valuable assistance in connection 

 with the titles of works in the Scandinavian, Hungarian, and Slavonic languages. 



L. FLETCHER, 



Director. 



BRITISH MUSEUM (NATURAL HISTOKY), 

 June 25tli, 1910. 



