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SECTION I. 



Tertiary Calcareous Marls. 



These are highly interesting in a twofold point of view : first, in 

 reference to our agriculture, as occurring in the midst of a region 

 of sandy soils where the greensand marl, lime, and other like 

 sources of fertility are remote; and secondly, in reference to the 

 progress of our scientific geology, from being the only tertiary 

 formations yet discovered in the State, and at the same time the 

 extreme northeastern limit of the very extensive range of the 

 . tertiary deposits of the Atlantic border of the middle and southern 

 States. 



The geology of these beds is at present somewhat obscure, 

 though the few fossils found prove that they belong to one of the 

 oldest periods of our tertiary formations. Their range is very 

 circumscribed, the only locality of much importance being near 

 the western corner of Cumberland county. Nevertheless, the 

 deposit demands a brief description from its economical value to 

 the neighbourhood where it occurs, and the clew which it may 

 furnish to corresponding strata in other sections of the sea- 

 board region of the State. 



These small insulated patches of tertiary, are evidently refer- 

 able by their fossils to the miocene epoch, notwithstanding the 

 disproportion of extinct over recent species. We can at present 

 enumerate only about thirteen clearly recognized species; twelve 

 of which are no longer in existence. Though this proportion 

 might rather imply an eocene date for the deposit, the number of 

 discovered fossils is too few to justify us in concluding this to be 

 the actual relation of the extinct to the recent shells; while on 

 the other hand, all the species are either identical with those of 

 the miocene of Maryland and Virginia, or exhibit a close analogy 

 of form. 



The position of the principal known tracts of tertiary in the 

 State, will be seen by consulting the geological map. 



The principal deposit of these tertiary marls occurs in Cum- 

 berland county, upon the upper part of Stow creek and its tribu- 

 taries, but whether it extends farther through the country, con- 



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