and Superior Formations of West Tennessee. 369 
face occupied by the group is about eight miles wide. It be- 
comes narrower as we follow it northward. (4,4, on the map.) 
The belt appears to be the northern extension of Hilgard’s 
“Flatwoods” region, the group itself forming the lower part of 
his “Northern Lignitic.” I have met with hard layers, “ rocks,” 
in this series containing shells, but as yet have found no deter- 
Along the Memphis and Charleston Railroad, the belt of sur- 
It b 
Tennessee. It occupies a belt about 40 miles wide, which runs 
in a north-northeasterly direction through nearly the central por- 
tion of this division of the State. (See map and section 5, 5.) 
As seen in bluffs, railroad cuts, gullies, and in nearly all expo- 
are met with. These often contain vegetable matter. Now and 
® This Journal, [2], xxvii. 363. 
Ax, Jour. Sci.—Srcoxp Serms, VoL. XXXVII, No. 111.—Mar, 1864. 
48 
