6 THE CANADIAN NATURALIST. [Vol. vil. 



certain guide, and to place our reliance on superposition and fos- 

 sils, will hesitate to give our adhesion to his views, except so far 

 as thej may be established by these other criteria, while at the 

 same time w-e must admit that Dr. Hunt has by his own labours 

 immensely increased the value and importance of chemistry as 

 an element in G;eolo2;ical reasoning's. Nor can there be any 

 doubt that the promulgation of Dr. Hunt's views, in his address 

 to the American Association last year, has given a new impulse 

 to the study of this subject; and in the coming summer manry 

 skilled observers will be engaged in putting to those ancient, 

 crumpled and mysterious rocks, w^hich underlie or are associated 

 with the fossiliferous rocks of Eastern America, the question, to 

 what extent they will respond to the claims made on their be- 

 half by Dr. Hunt. More especially we may look for much from 

 the researches of Sir William Lo2;an, who, released from the de- 

 tails of the business of the Survey, has been for some time ap- 

 plying his unrivalled skill as a stratigraphical geologist to the 

 further elucidation of the intricacies of the structure of the Eastern 

 Townships of the Province of Quebec ; and whose matured re- 

 sults, whether in strict accordance w^th those deduced from the 

 previous work of the Survey, or modified by his later researches, 

 will be of the utmost value with reference to the structure of the 

 whole of Eastern America. 



The recent discoveries in the fossils of the primordial rocks 

 have re-opened those discussions as to the terms Cambrian and 

 Silurian which raged some years ago, between the late lamented 

 Sir Roderick Murchison and his contemporary and survivor the 

 venerable Sedgwick. Dr. Hunt has ably reviewed the history of 

 this subject in the pages of the Canadian Naturalist^ with the 

 view of enquiring as to the best nomenclature for the present ; 

 and arrives at conclusions in harmony with those maintained by 

 Sedgwick many years ago. I confess that I have myself long felt 

 that the nomenclature introduced by the great authority of Sir 

 E-oderick and the English Survey, and followed somewhat too 

 slavishly on this side of the Atlantic, requires a reform, of which 

 indeed Sir C. Lyell has to some extent set the example in the 

 latest edition of his elements. When Sir Roderick Murchison 

 was preparing the last edition of his '• Siluria," I had some cor- 

 respondence with him on the subject, and ventured to urge that 

 he should himself revise the classification of that work, wishins; 

 at the same time to make similar changes in my " Acadian Geo- 



