764 JESSE E. HYDE 



nature of the formation/ but their sections are for the most part 

 of the Bedford, Berea, and Sunbury formations. At a few locaHties 

 only is more than the very base of the Cuyahoga described and in 

 no one section is the entire formation distinguished. 



From these observations it appears that there lies southwest of 

 the Vanceburg sandstone facies in Kentucky an area in which the 

 Cuyahoga is largely a bluish argillaceous shale, and that the 

 margin between them lies somewhere between 5 and 20 miles 

 south-southwest of Vanceburg, Kentucky. Not only do the sand- 

 stones that characterize the Vanceburg facies largely disappear, but 

 the red shales that are equally characteristic are replaced by bluish 

 ones. A sandstone member of precisely the same character as the 

 Buena Vista member on the eastern side of the Vanceburg facies and 

 occupying about the same position in the formation is continued 

 to the southwestward into this shale facies. It is quarried at 

 Farmer, Freestone, and Rockville, about 30 miles southwest of 

 Vanceburg, where it is about 25 feet thick and is reported underlain 

 by from i to 11^ feet of soft shales. Morse and Foerste consider 

 this sandstone the top of the Buena Vista member, using that 

 term with the sense given it by Prosser. Although it closely agrees 

 with the Buena Vista member (sense adopted by the present 

 writer) in structure and position, this correlation cannot, as yet, 

 be considered established. Within 10 miles farther to the south- 

 southwest, this member appears to pass into shales and the Cuya- 

 hoga is almost entirely a shale, but apparently with diminished 

 thickness. 



The question may well be raised whether these shales are the 

 equivalent of the Cuyahoga formation, as it has herein been de- 

 scribed, in southern Ohio. A careful tracing of the sandstone 

 members in the lower part is necessary to an opinion as to whether 

 the base is approximately the same. As to the upper limit, Al- 

 lerisma winchelli was found by the writer in the overlying yellow 

 sandstones, perhaps 100 feet above the shales, near Morehead, 

 Kentucky. This species is, as far as known, confined to the Byer 

 and Allensville members of the Logan. This would indicate that 



^"The Waverly Formations of East Central Kentucky and Their Economic 

 Values," Kentucky Geol. Surv., Bull. 16 (1912), 76 pp. 



