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PALAEONTOLOGY. 



would be formed there, but they are not; for no such fossils have 

 yet been found in granite. Probably no cause can be assigned for this, 

 although several opinions have been formed, such as granite being the 

 original matter prior to vegetable or animal ; which may be probable, 

 although we have no reason to suppose that the formation of granite is 

 different from all others." — P. iv. 



One of the latest acquisitions of knowledge — subversive of a generally 

 entertained idea in geology — bears upon the relative antiquity or priority 

 of the superficial masses of granite, porphyry, basaltic, and other 

 crystalline non-fossiliferous rocks, which, agreeably with that long 

 prevailing notion, were called ' primary formations.' 



Hunter alludes to the opinion as current in his time, viz. that 

 " granite was the original matter prior to vegetable or animal ;" but saw 

 " no reason for supposing that the formation of granite is different 

 from any of the others." — P. vii. The subsequent progress of chemical 

 science has proved that granite is a product of intense heat; and that, 

 like other crystalline rocks, it differs, in the cause of its formation, 

 from stratified fossiliferous rocks. But satisfactory proof, since Hunter's 

 time, has been obtained that some granites are not different in their 

 formation, in point of time, from strata that contain animal and 

 vegetable remains, but that they have been poured out since the deposi- 

 tion of the fossiliferous beds which have been upraised, distorted, or 

 metamorphosed by the heat of such more recently formed and intruded 

 crystalline rocks. 



I will here merely refer to the section in the twelfth chapter of the 

 fourth edition of Lyell's ' Principles of Geology,' headed " No proofs that 

 these crystalline rocks were produced more abundantly at remote 

 periods ;" and to the admirable memoir by the Duke of Argyll on the 

 tertiary age of certain basaltic strata in the Isle of Mull. Only an 

 accomplished modern geologist will be able fully to appreciate the mind 

 of Hunter, who in the last century, in reference to the then and long- 

 after prevalent belief that such crystalline rocks were ' primitive,' or 

 prior to the fossiliferous, or to vegetable and animal life, saw " no reason 

 to suppose such difference to exist." 



Hunter acknowledged, indeed, that he had obtained remains of sea- 

 animals from every kind of mineral, except the granitic or crystalline 

 rocks. But fragments of the greywacke slate, containing marine 

 organic remains, have recently been found entangled in the granite of 

 the Hartz, by M. de Seckendorf. 



" We find," Hunter proceeds to say, " the remains of sea-animals in 

 every kind of substance excepting granite. We find wood, bones of 

 sea-animals, bones of land-animals, in freestone, gravel, clay, marl, 



