GEOLOGICAL LITEllATURE OF THE VIRGINIA COASTAL PLAIN. 21 



The wide distribution of rich shell marl "of marine origin" throughout the Coastal 

 Plain of Virginia and Maryland is mentioned and the writer advocates the use of the 

 material as a fertilizer on exhausted soils. Cases are cited where the soil was rendered 

 much more productive by the addition of a thin layer of the shell marl. 



1833 



Conrad, T. A. Fossil Shells of the Tertiary Formations of America. 

 Vol. i, Nos. 1-3, 56 pp., 20 pis., Phila., 1832-35. Republished by G. D. 

 Harris, Washington, 1893. 



In this work molluscan fossils are described from Yorktown, Smithfleld, and Suffolk. 

 In the first part (No. 1) of the work the deposits in eastern Virginia are designated as 

 the Upper Marine or the Upper Tertiary while in the last part (No. 3) the same deposits 

 are called Medial Tertiary or Older Pliocene. In this latter part the Eocene is mentioned 

 as occurring in Virginia "forming the western boundary of the Pliocene." 



1833 



Conrad, T. A, On some new Fossil and Recent Shells of the United 

 States. 



Amer. Jour. Sci., vol. xxiii, pp. 339-346, 1835. 



Several new species of fossils from Yorktown, Suffolk, and Smithfield are described 

 from the "upper marine" (Miocene) formation. 



1834-5 



Conrad, T. A. Observations on the Tertiary and more Recent Forma- 

 tions of a Portion of the Southern states. 



Jour. Acad. Nat. Sci., Phila., vol. vii, pp. 116-129, 1834. 



The occurrence of the Eocene and "Pliocene" (Miocene) is noted along the James 

 River and the statement is made that the "Pliocene" deposits there contain Ostrea 

 compressirostra. 



Rogers, Wm. B. Some observations on the Tertiary Marl of Lower 

 Virginia. The Fanners Register, 1834-5. Reprint of Report on the 

 Geology of the Virginias, pp. 1-20, New York, 1884. 



In a letter to the editor of the Farmer's Register dated June 26, 1834, Professor 

 Rogers- reports the presence of greensand near Williamsburg, Kings Mill, and at Belle- 

 fleld, which he was hopeful would furnish as good greensand for fertilizing purposes as 

 that of New Jersey. In the Farmer's Register for 1835 the value of the shell marls near 

 Williamsburg and Yorktown for fertilizing purposes is discussed. The writer follows 

 Conrad in placing the Yorktown, James River, Smithfield, and Suffolk beds in the Middle 

 Tertiary. He also reports the presence of the Lower Tertiary or Eocene in Virginia 

 along the Potomac, Rappahannock, Pamunkey, and James rivers and described its litho- 

 logic characters. Cardita planicosta, Ostrea sellwformis, and Fusus longcEvis are said 

 to occur in great numbers in all localities examined and the entire fauna shows marked 

 relationships to the Eocene of Alabama, Paris and London. The greensand and gypsum 

 of the Eocene deposits are both said to be valuable for fertilizing purposes. 



