THE SHENA ND OA H LIMES TONE 657 



beds east of Churchville and in the buff and red slates at the 

 base of the formation in cuts two miles east of Staunton, Utica 

 graptolites occur in considerable abundance." 1 



Mr. Keith, apparently, did not have a very clear conception 

 of the lithological character of this formation for he states in his 

 description that "It consists of black and gray calcareous and 



FlG. 1. — Parson's quarry in Shenandoah limestone, near Martinsburg, W. Va. 



argillaceous shales of fine grain, and shows no variations within 

 this area." 2 It will be seen in the following description that 

 after the thin argillaceous shales in the lower part of the forma- 

 tion there are shales alternating with greenish micaceous sand- 

 stones. Again there is confusion in reference to the period to 

 which the formation belongs for in the description it appears 

 under the Cambrian, 3 and under the "columnar section" 4 and 

 legend of the map as Silurian. 



1 Geologic Atlas of the U. S., Folio 14, p. 2. 



2 Geologic Atlas of the U. S., Folio 10, p. 3. 3 Ibid., p. 3. 4 Ibid., p. 5. 



