126 FLORIDA GEOLOGICAL SURVEY-EIGHTH ANNUAL REPORT. 
and dunes, at the time the sea withdrew from the land, and are thus 
contemporaneous in age or nearly so with the marine shell marls. 
However, in ponds, streams and lakes fresh-water marls, sand and 
muck deposits accumulated which rest upon and hence are of some- 
.what later age than the marine marls, and it is in deposits of this 
kind chiefly, as would be expected, that the land, and fresh-water 
fossils are preserved. A more detailed account of a section through 
a stream bed at Vero will be given in connection with the descrip¬ 
tion of the fossil human remains. 
THE GEOLOGIC HISTORY OF THE FLORIDA EAST COAST. 
The geologic history of the Florida East Coast will be consid¬ 
ered in this paper only in so far as it affects the locality under dis¬ 
cussion. It is known that the' early Pleistocene included a period of 
great submergence during which the extensive marine marls and 
limestones of eastern and southern Florida were deposited. Fol¬ 
lowing the accumulation of these early Pleistocene formations the 
peninsula was lifted in relation to the strand-line to a level some¬ 
what above its present elevation. This period of probably slight 
emergence was followed by a depression, proof of which is derived 
from many sources and is conclusive. Shaler long ago noted the 
fact that the important harbors of Florida are flooded river valleys*. 
Vaughan likewise has called attention to the submerged channels of 
both the Atlantic and the Gulf Coasts which, together with other 
evidence, lead him to conclude that both the mainland and the 
Keys of the Florida East Coast stood at the time of maximum 
Pleistocene emergence as much as 30 feet above the present strand- 
lineP The existence of a Pleistocene cypress swamp in Hillsboro 
Bay, 20 feet below the present sea level, and of a peat bed at the 
same depth near the Florida Keys on the Atlantic Coast, has been 
noted by the writer. Additional evidence of changes of level may 
be adduced from physiographic features in the interior of the State, 
particularly from the lakes of the “Fake Region" of Florida, the 
basins of which probably originated through sinkhole formation at 
a time when the land area stood higher that at present.* The land 
*The Geological History of Harbors, U. S. Geol. Surv., 13th Ann. Rept. 
pt. 2, pp. 190-192, 1893. 
t Sketch of the Geologic History of the Florida Coral Reef Tract and Com¬ 
parisons with Other Coral Reef Areas, Washington Acad. Sciences, Vol. iv, 
P- 30, 1914- „ 
t Florida State Geol. Surv., Seventh Annual Report, p. 56, 1915; ibid., Sixth 
Annual Report, p. 155, 1914. 
