Feathers ton haugh s Geological Report. 63 



county, on the eastern shore of Maryland, beds of fossil shells 

 of various genera, with a very slight proportion of marly earth 

 strewed amongst them, rise from 15 to 20 feet by the water 

 side, whilst in other proximate localities extensive areas seem 

 to be formed of nothing but fossil oysters. Other localities, 

 containing a great profusion of these fossils, are found in the 

 vicinity of Piney Point, a summer bathing-place on the Mary 

 land side, about twenty miles from the mouth of the Potomac. 

 Fine exhibitions of this kind, also, are seen on the right bank 

 of James river, Virginia, extending southeast from the vicinity 

 of City Point, wherever the banks are high enough. Occasion 

 ally calcareous masses are found irregularly distributed beneath 

 the greenish argillaceous marls, containing the impressions of 

 shells only, as if their calcareous substance had been carried 

 below by the constant percolation of water. These appear 

 ances, varying with the localities, are common to all the shell 

 deposites of the tide-water districts of the Southern country, 

 and may be traced, associated with the subcretaceous beds, 

 the whole extent of the line defined by them. Little has been 

 done hitherto to class these various beds according to the 

 intelligent system proposed by Mr. Lyell. This is a task 

 requiring the devotion of much time, by individuals possessing 

 a minute knowledge of conchology, and which cannot be 

 achieved in a very short period.* 



The geological column, of which this slight sketch has been 

 given, finishes with the superficial soil upon which we live. 

 This consists either of the detritus of pre-existing beds brought 

 into its place by the agency of water, or of the decomposed 

 parts of rocks in place, the decomposition of which has been 

 effected by external causes. 



In the preceding pages it has been mainly the intention of 

 the writer to effect three things: to furnish some guide to 



* Mr. T. Conrad possesses the requisite qualifications, and has acquired ^ao 

 much local information of the Southern beds, that it would be comparatively easy 

 -for him to accomplish it. 



