Mr. Lyell on the Coal Field of Tuscaloosa, Ala. 373 
and cretaceous strata, to the older rocks of the Apalachian re- 
gion, without first crossing an intervening zone of the hypogene 
or granitic rocks. In the eastern part of the State, the crystal- 
line formations still appear, as at Wetumpka, where, as I learn 
from Prof. Brumby, the lower cretaceous rocks rest upon mica 
schist. But on going westward to the Cahawba River, and still 
farther west to the Warrior, at Tuscaloosa, we find the carbonif- 
erous strata concealing the granitic rocks, or coming into direct 
contact with the cretaceous. At the falls of the Warrior, at 
Tuscaloosa, beds of gravel containing well rounded pebbles of 
quartz, are seen to rest unconformably on the gray micaceous 
sandstone of the coal, which is full of Calamites and impressions 
of Lepidodendron and Sigillaria. I should have felt very doubt- 
ful respecting the true age of the overlying unconsolidated gravel 
~ and sand, in which no organic remains have yet been discovered, 
in that nieighberhood, if I had not carefully examined the position 
of similar beds of loose gravel 30 feet thick, at Montgomery, 100 
miles southeast, on the Alabama River, as also at spots between 
Montgomery and Wetumpka. In nodules of an impure lime- 
stone, in a loam overlying that gravel, and almost in contact, I 
Sonal casts of Inoceramus, Rostellaria arenarum, and other com- 
mon chalk fossils. They are well seen at the bluff, in the sub- 
urbs of Montgomery, and there are beds of gravel, and various 
colored sands and clays below them ; the general dip of the cre- 
taceous strata being to the south, dhiibls brings up the edges of 
certain calcareous marls, newer than the gravel, but of the same 
epoch, producing prairie soils, often destitute of natural wood, 
which nn for a great distance east and west, or in the line of 
crossing the Alabama several miles south of Mont- 
omery, and being again seen in their western prolongation on 
the Tombecbee, at Arcola and other places. It is due to Mr. 
Conrad, to state that in an outline map which he presented to me 
in 1842, with permission to publish any part of it in my general 
map, he had traced out the course of the lower cretaceous beds, 
especially their northern boundary in Alabama, with great ap- 
proach to accuracy, from observations made by him, and infor- 
“mation obtained during his tour in 1833. 
The ‘members of the carboniferous series, which I examined 
in an excursion with Prof. Brumby, within a distance of between 
Sxcoyp Series, Vol. I, No. 3—May, 1846. 48 
