MEMOIRS 



OF THE 



GEOLOGICAL SUEYEY 



THE UNITED KINGDOM. 



ILLUSTRATIVE OP 



BRITISH ORGANIC REMAINS. 



DECADE XI. 



TRILOBITES. 



(chiefly SILUIlIAjS\) 



PUBLISHED BY OBDER OF THE LORDS COMMISSIONERS OF HER MAJESTY S TREASURY. 



LONDON: 



PRINTED FOR HER MAJESTY'S STATIONERY OFFICE 



PUBLISHED BY 



LONGMAN, GREEN, LONGMAN, EGBERTS, & GREEN; 



AND BT 



EDWARD STANFORD, 6, Charing Cross, S.W. 



1043.5. 



1864. 



