100 FISHES OF TUE SILURIAN ROCKS, 



FISHES OF THE SILURIAN ROCKS, 

 UPPER AND LOWER.* 



THEIR RECENT HISTORY, ORDER, AND SIZE. 



But the system of the Old Red Sandstone represents the se- 

 cond^ not the first, great period of the world's history. There 

 was a preceding period at least equally extended, perhaps 

 greatly more so, represented by the Upper and Lower Silu- 

 rian formations. And what is the testimony of this morn- 

 ing period of organic existence, in which, so far as can yet 

 be shown, vitality in the planet which man inhabits, and of 

 whose history and productions he knows anything, was first 

 associated with matter 1 May not the development hyjjothesis 

 find a standing in the system representative of this earliest 

 age of creation, which it fails to find in the system of the Old 

 Red Sandstone 1 



It has been confidently asserted, not merely that it may, 

 but that it does. Ever since the publication, in 1839, of Sir 

 Roderick Murchison's great work on the Silurian system, it 

 had been known that the remains of fishes occur in a bed of 



* This is the chapter referred to in the prefatory remarks as liaving 

 been intended to be remodelled by the author. Those portions which are 

 no longer in accordance with fact are enclosed in brackets : the other 

 parts may be accepted as correct. — L. M. 



