•10 The Upper Cretaceous Deposits of Maryland 



Mitchell, Samuel L. Cuvier's Essay on the Theory of the Earth. 

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1820 

 Hayden, H. H. Geological Essays; or an Inquiry into some of the 

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1821 



Troost, G. Description of a variety of Amber and of a Fossil Sub- 

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Amer. Jour. Sci., vol. iii, 1821, pp. 8-15. 



1824 

 Finch, John. Geological Essay on the Tertiary Formations in 

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1825 



Troost, G. Description and Chemical Analyses of the Eetinasphalt 

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1827 

 Morton, S. G. Description of a new species of Ostrea; with some 

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1828 



Morton, S. G. Description of two new species of Fossil Shells of the 

 genus Scaphites and Crepidula: with some observations on the Ferru- 

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Jour. Acad. Nat. Sci. Phila., vol. vi, 1828, pp. 107-119. 



