300 E. A. Smith—Geology of Florida. 
Heilprin, and by him pronounced to be of Vicksburg age, 
Orbitoides Mantelli being prominent among the fossils. 
In many places near the coast in Wakulla County, a very 
finely pulverized white marl is mingled with the sand, impart- 
ng to it a great degree of fertility ; this is the “Gulf Ham- 
mock” land of which much has been written. From enquiries, 
rom the observations of Conrad and others, I learn that 
these “ Hammocks” exist all along the coast from Wakulla, 
ampa Bay. This marl is also of Vicksburg age where 
have examined it, and from descriptions which I have had 
from various sources, it seems almost certain that the marls of 
the Gulf Hammocks in the other counties named, are of the 
same geological age. In Jefferson, Madison and Hamilton 
Counties, the Vicksburg limestone underlies the Stratified Drift 
everywhere, as may be seen in its outcrops along the banks of 
is still the underlying rock, the surface covering being here 
light colored sands chiefly—the yellow and reddish sands and 
loans of the adjoining counties westward, being usually ab: 
sent. Specimens of the limestone with characteristic fossils 
have been collected in the vicinity of Live Oak, and an earthy 
limestone, the counterpart of some of the Vicksburg limestone, 
in which, however, no fossils were observed, was noticed by 
.me near Lake City and thence out near to the Suwannee shoals 
on the river of same name. I am informed that the rock at 
the shoals is highly fossiliferous. At the time of my visit! 
was hidden by high water. : 
The Suwannee River, which has its head waters partly 1m 
Okefinokee Swamp in Georgia flows through most of its cours® 
in Florida, between banks of Vicksburg limestone, and sev- 
eral large sulphur and limestone springs break out through 
crevices in the rock along the river. 
A bed of what I suppose is Zignite has been found lower 
down the river; the exact locality I could not learn; ut @ 
large quantity was raised some years ago, and experiments, 
with unfavorable results, made with it in Tallahassee, to test 
its fitness as a material for the manufacture of illuminating 8% 
