GEOLOGIC SECTIONS ACROSS THE EVERGLADES. 71 
much as two feet in thickness, containing broken vertebrate re¬ 
mains fill in the irregularities at the top surface of the Caloosahat¬ 
chee marl. Just above Labelle the shell marl (No. 2) is absent, the 
calcareous stratum resting upon the blue sandy clay marl. The 
unconformity, however, is plainly seen being indicated at this local¬ 
ity by well worn rock fragments. 
‘ The extension of the Caloosahatchee marls to the northeast has 
been shown by collections made by Mr. H. G. Hayes from the 
banks-of the St. Lucie Canal northeast of Lake Okeechobee. 
T- ■ - 
FORT THOMPSON BEDS. 
While the deposits lying above the Caloosahatchee Marl in the 
vicinity of Labelle and Fort Thompson have been referred to by 
several writers they have not previously been described in detail 
owing, perhaps, to imperfect exposures. The excavations that 
have now been made, however, afford the opportunity of examin¬ 
ing these deposits at several localities between Fort Thompson and 
Lake Okeechobee, as well as in the Everglades. The following 
section of these deposits is found just below Goodno’s Landing, 
Fort Thompson. 
3. Fresh water limestone 2 feet. 
2. Marine shell marl y 2 foot. 
1. Fresh water shell marl 3 feet. 
The Caloosahatchee marl, as may be seen by continuing the 
section down stream, either lies immediately below the fresh water 
shell marl, No. 1, of the section, ofi is separated from that marl by a 
marine shell marl. By continuing the section up stream it is found 
that a marine shell marl rests upon the fresh water limestone, and 
that this in turn gives place to a fresh water marl. 
To these deposits consisting of alternating fresh and brackish 
water and marine marls and limestones is here applied the term, 
the Fort Thompson Beds, the tvpe exposure of which is at Fort 
Thompson. 
The fresh water limestone of this formation was referred by 
