and Superior Formations of West Tennessee, 363 
bighee sand of Hilgard, which most likely ought to be included 
in his Hutaw Group. Its outcrop occupies a belt of territory 
varying from about two to eight miles in width, and running 
more than half way through the State.“ (See 1, 1, on the map.) 
As before stated, the Tennessee, in the southern part of the 
State, strikes this group. The river here washes the sand, along 
its western bank, for eighteen or twenty miles and presents us, 
at intervals, with several bluffs that exhibit interesting sections. 
to 100 feet in 
the gravel bed described. The principal ones, (indicated on the 
map by short heavy lines,) are the Coffee Bluff; sometimes 
> 
With in the series. It very generally contains woody fragments 
and leaves converted more or less into lignite. Silicified trunks 
Of trees are not uncommon. The maximum thickness of the 
~y in Tennessee is not known; it is probably not far from 
t 
eet. 
A section of the bluff at Coffee may be taken as a type of the 
materials and stratification of this group. 
4. On top ; gravel and ferruginous conglomerate. 
8. Sands, with thin laminz of slaty clay; much like No. 1 below. 10 feet. 
2. Slaty clay, with but little sand; contains fragments of wo 
_ and leaves, ; 
- Grey and yellow sands, interstratified with numerous thin 
aminz and some thicker layers of slaty clay; strata of sand 
Oceasionally from three to six feet without clay. Leaves, in 
agments, and pieces of lignitic wood abundant. — Projecting 
from the mass are the ends of two large trunks, their bark con- 
verted into lignite and their wood silicified. — : 
Contains pyrites and yields proto-salts of iron and ferrugin- 
ous waters, 
Extending to the water's edge. ‘ . - 65 feet. 
20 feet. 
‘ ‘ ec A : 
There is some i rd to the northern limits of this and the succeeding 
Brae (No. 2.) a ioe. onan upon the map by the broken lines bounding the 
ne limi satisfactorily known as far as the lines continue un- 
: but beyond this they are not easily determined and require more examina- 
tion, outline given is probably not far from the correct one. 
