PREFACE. 



In the earlier Guides to the Geological Department the great 

 section of the Invertehrata, the Fossil Plants, the Historical and 

 Stratigraphical collections occupied not more than 24 pages with 

 their description. The work of naming, preparing, and arranging 

 the infinite number of specimens exhibited in the four Galleries 

 devoted to these collections, has only of late been so far completed 

 as to admit of a full account being prepared. Many years of 

 detailed work are still required to perfect this extensive series. 



In the preparation of this new Guide I have been most kindly 

 assisted in the Cephalopoda by Dr. A. H. Foord and Mr. G. C. 

 Crick; in the other Mollusca, by Mr. E. Bullen Newton and 

 Mr. G. F. Harris; in the Brachiopoda, Echinoderma (general), 

 Cystidea, Blastoidea, and the Crinoidea, by Mr. F. A. Bather; 

 in the Bryozoa, Echinoidea, Asteroidea, Ophiuroidea, Ccelentera, 

 and Vermes, by Dr. J. W. Gregory ; in the Porifera, Eadiolaria, 

 and Foraminifera, by Dr. G. J. Hinde ; in the Fossil Plants, by 

 Mr. A. C. Seward ; and in the general arrangement, by Mr. A. 

 Smith Woodward. 



Thanks are also due to the Delegates of the Clarendon Press, 

 University of Oxford ; the Palseontographical Society ; to Messrs. 

 A. and C. Black ; to Messrs. William Blackwood and Sons ; 

 to Messrs. Cassell and Co., and to Messrs. Macmillan and Co., 

 for the loan of many of the illustrations used in this Guide. 



HENRY WOODWARD. 

 Geological Department. 

 16th February, 1897. 



