78 Upper Cretaceous Fauna from Tennessee [276 



graphically lower than that along Owl Creek in Mississippi. 

 At the latter locality the fossiliferous horizon is in the upper- 

 most beds of the Eipley and is directly overlain by Eocene 

 limestone. 8 Below the Owl Creek beds is the southern equiv- 

 alent of the McNairy sand member of the Ripley formation. 9 

 The McNairy sand member,, together with about 100 feet 

 of sparsely fossiliferous, ferruginous Ripley clay, lie strati- 

 graphically higher than the Coon Creek horizon and are 

 exposed to the west of it. (For cartographic relations of the 

 two localities see sketch map in Fig. 1.) Thus, it is quite 

 evident that the Coon Creek fauna is older than the Owl 

 Creek fauna. 



DESCRIPTION OF THE LOCALITY AND CHARACTER OF THE 

 SEDIMENT 



A thickness of more than thirty feet of the fossil-bearing 

 beds is exposed along the banks of Coon Creek. For one-third 

 mile this stream flows in a narrow V-shaped channel from 

 six to fifteen feet deep which has been cut out during the 

 last twenty years. The stream has a steep gradient and its 

 channel is deepened by every heavy rain. The channel fills 

 quickly after a thundershower and its sides are kept freshly 

 scoured by the rushing water. White shells of Crassatellites, 

 Cucullaea, Cyprimeria, Gryphaea, Ostrea, Drilluta, Lunatia, 

 Baculites, etc., project out of the dark greyish blue matrix 

 and glitter in the clear water and the sunshine. In general 

 aspect the exposure bears a striking resemblance to certain 

 Tertiary beds. In broad physiographic relations, character of 

 the matrix and whiteness of the shells, the Coon Creek locality 

 resembles the well-known Upper Cretaceous exposure of 

 Brightseat, Maryland. This locality is two miles east of Dis- 

 trict Line and has yielded the most prolific Upper Cretaceous 



8 Harris, G. D., The Midway Stage, Bull. Amer. Pal, vol. 4, no. 4, 

 1896, p. 24. 



'Stephenson, L. W., Paper given before the Paleontological So- 

 ciety of America, December 29, 1916. 



Lowe, E. N., Geology of Mississippi, Bull 12, 1915, p. 62. 



