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0» the Foc/is said to he older than the oldest Fossiliferons 

 Deposits. 



Mr Lyell. in his Travels in North America, states, in the 

 following terms, his opinion as to the non-existence of Primi- 

 tive Rocks. 



As it is still a favourite theory of many geologists, that the gra- 

 nite and other formations, both stratified and unstratified, which 

 I have called hypogene, were produced in far greater abund- 

 ance before the origin of the oldest strata at present known to 

 contain fossils than at any subsequent period ; and as some are 

 disposed to consider their conclusions on this head much 

 strengthened by the fact that, in North America, as in Europe, 

 there are certain points Avhere granite, mica- slate, and gneiss, 

 can be shewn to be of prior date to any of the fossiliferous rocks 

 hitherto detected, — I shall briefly refer to the leading arguments 

 against this doctrine, which I have advanced both in my 

 " Principles" and " Elements of Geology." 



The crystalline formations, such as granite and gneiss, were 

 termed primitive and primary by some of the earlier observers, 

 because in each district they are the lowest in geological posi- 

 tion. It is now understood, in regard to granite, syenite, and 

 the unstratified class, that they are of various ages, often 

 newer than fossiliferous strata ; and that it by no means follows 

 that they were first in the order of time, because they are in- 

 ferior in position. Paradoxical as the first statement of this 

 proposition appears, it is now acknowledged that the super- 

 structure is often older than the foundation on which it rests, 

 the latter having been forced up subsequently from below, 

 either in a solid form, or, more frequently, like lava in a volcano. 

 It is also now admitted, in direct contradiction to all precon- 

 ceived opinions, that many stratified hypogene formations, the 

 gneiss, mica-slate, talc-slate, and saccharine marble of the 

 Alps, Apennines, and other districts, have assumed their crys- 

 talline texture after the origin of many of the fossiliferous 

 strata ; even in some cases long after the deposition of those 

 which repose directly upon them. 



Nevertheless, if avo confine the term primary to all I'ocka 

 which we can prove to be of older date than strata in which 



