114 The American Naturalist. [February, 
with bone implement; shell gouge (broken) 2 feet down; rude 
arrow-head on fire-place, 44 feet down; flint flake 5 feet down ; 
arrow-head lying on fire-place, at a depth of 6} feet from sur- 
face ; portion of arrow-head on fire-place, bearing marks of fire 
at a depth of 8 feet; fragment of bone awl 9 feet 9 inches 
down ; rude bone awl 10 feet down; bones of edible animals, 
mainly of alligator, deer and turtle, at all depths. 
EXCAVATION IV. 
At margin of base north-east portion of mound. Trench 
113x10x6 feet deep at end. A piece of coquina, smooth 
on one side, evidently used for polishing, at a depth of 2} feet, 
and a fragment of arrow-head with the usual bones of edible 
animals, were the only objects of interest met with. 
As before stated, absolutely no pottery was seen in the exca- 
vation, and this, with the 600 feet of swamp between the 
mound and the river, would argue for Mt. Taylor a place 
among the earliest shell heaps of the St. John’s. It was the 
habit of the builders of the shell heaps where solid ground was 
to be found, to locate their refuse heaps upon it, and it seems 
unlikely that a spot so far distant from the river’s edge as is 
Mt. Taylor to-day, should have been selected. It is a much 
more likely hypothesis that the swamp is the result of a 
change of channel in the river, and has formed since the 
abandonment of the mound. Professor Wyman has graph- 
ically described in his memoir (page 83 et. seq.) the manner of 
formation of similar swamps. The time required to trans- 
, form a portion of the river into swamp-land, the writer of this - 
paper believes to be somewhat less than is generally supposed, 
owing to the great abundance of floating vegetation upon the 
river. At Little Orange mound, opposite Lake Dexter, is a 
- steam boat wharf in use within eight years, according to’ the 
owner of the place. At present, masses of vegetation extend- 
ing some distance into the river have made access impossible _ 
for a boat of any draught, and are speedily forming the 
nucleus of a future swamp. 
_ Assuming this hypothesis of the formation of the swamp 
after the completion of the mound to be correct, an indication 
