12 TEANSACTIONS OF THE [1888 



appear in the deep ravines and wells all the way down to near 

 Swan Point and Rock Hall. Keeping on, in a generally south- 

 west direction, the formation reappears on the opposite side of 

 Chesapeake Bay, at Rock Point in Anne Arundel county, 

 crosses to near the head of the Magothy river, continues on to 

 the Severn river south of Cedar Point, extends from thence 

 across the county near the fork of the Patuxent river, and 

 after crossing Prince George's county, reaches the Potomac 

 river about six miles south of the District of Columbia. 



The southeastern limits of this formation are much less dis- 

 tinctly exposed, so that the line, as far as it has been possible to 

 trace it out, is very irregular, and in places rendered uncertain 

 by the absence of well exposed sections. An irregular line 

 beginning at the Delaware State border, about one mile south 

 of the head of Sassafras river, in Kent county, and running 

 from thence to a short distance from the mouth of the Chester 

 river below Rock Hall, and then diagonally across Chesapeake 

 Bay to behind Sandy Point, and keeping on across Bay Ridge, 

 is finally lost to view near the mouth of South river, in Anne 

 Arundel county. 



The Cretaceous terrane is greatly denuded along the shores 

 of Chesapeake Bay, in Anne Arundel county; likewise in 

 Kent county from near the mouth of the Chester to near the 

 head of Sassafras river. 



The formation as a whole has a gentle dip southeastward of 

 less than ten degrees. Nevertheless, in some places, as on the 

 Severn, at the southern end of Round Bay, and near the mouth 

 of Sassafras river, the strata appear almost horizontal. The 

 width of the formation may be stated as approximating an 

 average of nearly ten miles, but it is cut through by the 

 encroachment of Chesapeake Bay between the Eastern and 

 Western Shores. 



As in New Jersey, the Laminated Sands form the base of 

 the series, and on both shores of Maryland the beds are com- 

 posed of very fine white sand, carrying laminae of compact drab 

 or pale brown clay. In these aluminous layers the fossil remains 

 of vegetable matter lie closely packed in great abundance. Films 

 of the leaves of willows, sassafras, viburnum (?), and of many 



