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mentary system of rocks; during the deposition of which it has 

 been supposed man came into existence, simply because his 

 remains are principally found in the superficial part of the series. 

 These rocks constitute a large proportion of the dry land of 

 Europe ; and there are abundant evidences that they are, com 

 paratively speaking, of recent origin, and that a great por- 

 tion of the dry lands now forming Europe and Asia, have been 

 raised from the sea since they were exposed to a hotter climate. 

 The chalk of Europe, the oolite of the tropics, and the coal 

 formation of the south temperate, may be all of the same age ; 

 hence it will be observed that the present mode of distinguish- 

 ing these rocks is only applicable in certain localities, in the 

 same parallels of latitude. 



Sir H. De la Beche very justly remarks that " classifications 

 entirely founded on organic remains are at all times liable to be 

 erroneous, if contemporaneous deposition be thence inferred as 

 a necessary consequence, as we have had occasion to observe ; 

 they therefore may be considered as doubly liable to error when 

 employed in proving contemporaneous origin in such rocks as 

 those of 'the supracretaceous period." 



Palms and crocodiles are found in these deposits, analogous 

 if not identical to those now found in Africa and in the neigh- 

 bourhood of the Nile. That a great number of organic beings 

 should have become extinct during such great oscillations of the 

 earth's surface is a very natural supposition ; it is more surpri- 

 sing that so many of the grand stock should have been preserved 

 amongst the numberless vicissitudes of climates, and the sepa- 

 ration of continents into islands, and vice versa. 



The last group of sedimentary beds pass so insensibly into 

 the superficial alluvial deposits that no line of demarcation can 

 be drawn; we shall therefore close this subject by observing, 

 that the alluvial and loose accumulation of sands, &c. covering 

 the indurated sedimentary beds in Europe, contain principally 

 organic remains belonging, or indigenous, to the zone in which 

 they are now found. As this part of the subject is so well 

 described in almost all geological works, we must beg refer- 

 ence to them, trusting that the outline we have given here is 

 sufficient to show the agreement in the order of the sedimentary 

 rocks with the action of the northerly movement of the magnetic 



