PEBBLE PHOSPHATE DEPOSITS. 
8l 
The fossil vertebrates identified by Dr. Leidy from the river 
pebble phosphates on Peace Creek, include the following:* Tapirus 
terrestris (T. americanus) ; Equus sp.; Hippavion ( Hippotherium ) 
ingenuum; Hipparion plicatile; an upper molar tooth compared with 
Bison americanus; Antler bones and teeth of deer not differing from 
those of O do coileus ( Cermis ) virginianus; Elephas columbi; Ckla- 
mytherium septentrionalis {Chlamyd other ium humboldtii) ; dermal 
plates resembling those of Hoplophorus euphractus; Glyptodon peta - 
lifer ous; Megalonyx jeffersonii; Man at us antiquus; several ceta¬ 
ceans; Emys euglypha; one or two species of Trionyx; Testudo 
eras sis cut at a; two vertebrae of a large serpent; dermal plates of a 
crocodile; Ephippus gigas; dermal turbercles of ray; and teeth of 
Diodon, Myloiobates, Oxyrhina, and Galeocerdo. 
Of the species of this list several evidently represent fossils 
washed in from the Alum Bluff and Bone Valley formations through 
or into which the stream has cut its channel. This applies to some 
at least of the fish teeth. The Hipparion remains in these beds are 
probably also derived from the older formations. The teeth of 
this horse are quite resistant to erosion and although rather numer¬ 
ous in the Peace Creek beds it is probable that they have been car¬ 
ried into the deposits either from the reworking of Pliocene stream 
deposits immediately along the river or from the land pebble phos¬ 
phate deposits, across which the stream flows and in which Hippa- 
rions are found. This view is supported by the fact that the teeth 
of Hipparion are found in the deposits in all stages of erosion, in 
many instances reduced to a mere fragment of their former size. 
Moreover, Hipparion in association with the Pleistocene fauna is ob¬ 
tained in Florida only from those streams that cut across Pliocene 
beds. At some other localities, notably at Vero in St. Lucie County, 
the Peace Creek Pleistocene vertebrate fauna is found in a stream 
that flowed across early Pleistocene shell marl deposits. From this 
locality no Hipparion remains have been obtained. 
ALAFIA RIVER. 
Pebble phosphates similar to those in Peace Creek, are found 
and have been worked to some extent on the Alafia River. This 
stream originates in the land pebble phosphate area of Polk County 
^Description of Vertebrate Remains from Peace Creek, Florida. Wag. 
Free Inst. Sci. Trans. Vol. 2, pp. 19-31*, 1889. , 
