66 FLORIDA GEOLOGICAL SURVEY-EIGHTH ANNUAL REPORT. 
The second left peripheral (pi. 2, fig. 5) extends 35 mm. from 
the free border and 33 mm. along the border. Its thickness at 
the anterior inner angle is 12 mm.; at the posterior inner angle, 
18 mm. The upper surface is concave from the free border to the 
suture with the costal plate; the lower surface convex. The other 
left second peripheral (3426) is not so wide from outside to in¬ 
side and is somewhat thicker than the one with the number 3423. 
On the upper surface of these two peripherals the ridges in front 
of the intermarginal furrow are much broken up and irregular; 
behind this furrow they run parallel with the free border; above 
the longitudinal furrow they run at right angles with this furrow. 
The right third peripheral (pi. 2, fig. 6) has lost a part of its 
hinder inner border. The length along the free border is 37 mm. ; 
along the front border 37 mm. The thickness at the front end is 
21 111111.; of the hinder end at the free border, 26 mm. The thick¬ 
ening at the hinder end of the bone is to provide for the buttress 
from the hyoplastron. The ornamentation of the three scutal 
areas is different. Above the longitudinal furrow there are de¬ 
scending ridges. I11 front of the intermarginal furrow there are 
irregular and anastomosing ridges; behind this furrow, there are 
longitudinal ridges. 
The left ninth peripheral (pi. 2, fig. 7) has the free border 32 
mm. long. The extent of the front border is 41 mm.; the great¬ 
est thickness on the latter 10 mm. From the upper or inner bor¬ 
der to the free border the bone flares upward somewhat. The free 
border is thin and acute. Near the front end of the border for 
union with the sixth costal is a considerable pit for the end of the 
rib. Above the longitudinal furrow there are tubercles arranged 
in rows at right angles with one another. In front of the inter- 
marginal furrow the interrupted ridges are parallel with the fur¬ 
row ; behind it they are directed outward and backward. 
TRACHEMYS? DELICATA, NEW SPECIES. 
Plate 7, fig. I. 
Type-specimen . — A right fourth costal plate, No. 3738 of the 
Florida Geological Survey. 
Type-locality and formation .—Near Labelle, Lee county, Flor¬ 
ida. Pliocene? 
Diagnosis .—Carapace rather large, a foot or more in length; 
the neurals thick, the costals thin beyond the neural end. Scutal 
