TO 



SIE RODERICK IMPEY MUKCHISON, BART,, K.C.B., 



MEMBER OF THE INSTITUTE OP FEANCE, DIEECTOE-GENEEAL OF THE GEOLOGICAL SURVEY OF 



GREAT BRITAIN AND IEELAND. 



&c. &c. &c. 



DEAR SIR, 



I thank you for permission to dedicate the THESAURUS SILURICUS 

 to you. It was a request equally natural to make and to grant. 



I need not say that your kind approval of the execution of this humble but 

 laborious work is of the greatest value to me. 



The enjoyments of elegant life you early chose to abandon, preferring to wander 

 for many successive years over the rudest portions of Europe and Asia regions 

 new to Science in the hope, happily realized, of winning new truths. 



By a rare union of favourable circumstances, and of personal qualifications 

 equally rare, you have thus been enabled to become the recognized Interpreter 

 and Historian (not without illustrious aid) of the Silurian Period the grandest of all 

 the Periods, and, as yet, apparently the seed-time of all succeeding life. 



I do not now speak of your brilliant services in other fields of geological 

 research : my sole present object is to give expression to my abiding gratitude for 

 the active interest you have been pleased to take in the THESAURUS SILURICUS. 



I am, dear Sir, 



Respectfully and faithfully yours, 



J. J. BIGSBY. 



Gloucester Place, Portman Square. 

 1868. 



33V 



