FOSSIL INVERTEBRATED ANIMALS. 521 



from which such reveries proceed, and smile at the credulity 

 which believes them. 



It cannot, moreover, have escaped our readers, that equally 

 satisfactory conclusions are not deducible from all the fossil 

 remains found within the bosom of the earth. The extinct 

 genera, especially those of quadrupeds and reptiles, speak 

 pretty clearly in favour of the succession of formations, and of 

 different, though not exactly defined, eras. But it is not so with 

 most of the others. From the fish, for instance, httle can be 

 concluded as to the order of succession ; and, except a few 

 genera of the ancient strata, as little from the remains of mol- 

 lusca, Crustacea, and radiata. It may be added, too, that there 

 is much doubt respecting distinction from, or identity with, 

 living species, as to many of these aquatic remains ; nor is it 

 possible to pronounce with certainty respecting the extinction 

 of genera^ even, and much less of species : for who has explored 

 the profound abysses of the ocean — who can classify, and name, 

 and number, all its inhabitants ? 



And, after all, are we much more enlightened respecting the 

 recesses of the earth itself? What proportion does the degree 

 to which we can penetrate bear to the diameter of the globe ? 

 Who can tell whether the impassable granite constitutes a 

 solid nucleus of this planet, or reposes itself on other strata, 

 concealing marvels as great as those with which we are already 

 acquainted ; but, unlike them, destined peradventure to remain 

 for ever impenetrable to human investigation ? Again, how 

 small a part of the crust of the earth has been examined, and 

 what proportion doesthat part bear to its entire superficies ? 

 And, lastly, have geologists been invariably successful in disen- 

 tangling the confusion of strata in numbers of localities^ and in 

 accounting for the causes of such confusion ? 



These queries serve to show the extreme folly and presump- 

 tion of theorizing on a grand scale, so much the fashion with 

 the philosophers of the last century. Knowing next to nothing 

 of the mere superficial crust of this earth, both in extent and 



