AGE OF THE UNDERLYING ROCKS OF FLORIDA IO3 
At. Fort Myers 400 feet of the sediments are referred to the Mio¬ 
cene, at Okeechobee a slightly greater thickness and at Marathon 
nearly as much. This is based on the reference of these scattered 
foraminifera to the known Miocene of the northern part of Florida, 
perhaps not a safe comparison in consideration of the distance. 
However the Miocene of the Choctawhatchee Marl is similar in 
many respects and furnishes numerous species. The Jacksonville 
Miocene shows no ForanHinifera but Miocene is indicated in the St. 
Augustine well. 
PLIOCENE. 
None of the wells give definite evidence of the presence of the 
Pliocene with the exception of Okeechobee, although this is prob¬ 
ably present, especially in the southern part of the State between the 
Pleistocene and the Miocene. The fauna of the Caloosahatchee 
Marl is tropical in character and forms an excellent basis for com¬ 
parison, but unfortunately little was found in the well samples to 
compare with it. 
PLEISTOCENE. 
The Pleistocene in the southern wells is indicated to some depth, 
41 feet at Okeechobee and 78 feet at Marathon but little informa¬ 
tion is available from the other well samples. 
