I 



314 



TRANSACTIONS OF THE 



REVIEW OF GEOLOGICAL PHENOMENA, AND THE DEDUC- 

 TIONS DERIVABLE THEREFROM, IN TWO HUNDRED AND 

 FIFTY MILES OF SECTIONS IN PARTS OF VIRGINIA AND 

 MARYLAND. ALSO NOTICE OF CERTAIN FOSSIL ACOTY- 

 LEDONOUS PLANTS IN THE SECONDARY STRATA OF FRE- 

 DERICKSBURG. By Richard C. Taylor. 



I CONTRIBUTE towards the illustrations of Mr Clem- 

 son's and my own papers on the Mineralogy and Geo- 

 logy of this portion of North America, four sections, 

 which, with some investigations that are detailed but not 

 reduced into the diagram form, exceed the extent above 

 announced. 



The southern section in the parallel of Richmond, I 

 have already described ; pi. 16, fig. 3. The central 

 longitudinal section in the parallel of Fredericksburg, in- 

 cluding the gold region, and extending to Winchester, 

 is detailed in pi. 17, fig. 2. And the northern section, in 

 the parallel of Harper's Ferry, extending towards Bal- 

 timore, is delineated in fig. 1 of the same plate. A 

 fourth section furnishes details of the Union Gold Mining 

 company's tract in the vicinity of the Rappahannock 

 river. 



The observations I have now, individually, to make, 

 shall be few and condensed ; and chiefly in relation to 

 the Fredericksburg section. 



Avoiding all details, I proceed to give an abstract of 

 the four principal classes of rocks crossed by this section 

 of seventy-one miles; commencing with the lowest, and 

 at the east end. 



I. Primitive. — Extends westward from near Freder- 

 icksburg twenty-one miles, being subdivided into 



