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covery in this city of ferruginous sand and marl, obtained 

 by boring, from a depth of fifty feet and more ; which, on 

 examination, I found to correspond in most respects with that 

 of the Claiborne strata. 



" The fossil contents of these beds could not have been 

 deposited in a very tranquil sea, for many of them are 

 broken, their parts in separate situations, and much water- 

 worn. In different parts of the series there are to be seen 

 certain genera and species, which have been deposited in 

 great abundance, and in groups ; but the same genera and 

 species, both in anterior and posterior situations, are to 

 be found scattered, more or less profusely, throughout the 

 series. It is probable, therefore, that these fossils were 

 contemporaneous, forming but one system of organization, 

 and would have been equally numerous in every part of the 

 series, if the proper circumstances had existed. 



" Some important changes have, however, occurred 

 during the lapse of time in which these beds were formed. 

 One is very manifest in regard to a certain species of 

 Turritella, which, in the lowest bed, is found to be three 

 inches in length, but in the middle beds its standard 

 dimension is only one-and-a-half inches. 



" It is, moreover, observable that there are no remarkable 

 derangements in the sequence of geological events here 

 exhibited so as to require the admission of anv extra- 

 ordinary agency to explain their occurrence. With the 

 exception of a few terrestrial mammalia these fossils are all 

 of a marine kind. The lower beds, which more especially 

 abound with oysters, were evidently formed in comparatively 

 deep water ; higher up in the series, as it became more 

 shallow, we find a predominance of littoral shells; still 

 higher in the succession, we discover an evident preparation 

 for the dry hind to appear. 



" I obtained from these deposits, last summer, upwards 

 of fifty new species of fossils, in addition to those wlncn 

 had been previously obtained. 



" Some of these belong to extinct genera of terrestrial 

 mammalia, consisting principally of spinal bones. One is 

 a single vertebra, from a stratum of chalky limestone, three 

 and a half inches in diameter, with the spinal process and a 

 portion of the ribs attached : it probably belongs to one of 

 the larger Mastodon species. 



" I also obtained from the same place a naked vertebra, 

 about half the size of the former, but of a very different 

 species. 



