VERTEBRATA AT VERO. 
47 
ends of course are inserted into the peripherals, are for considerable 
distances left uncovered by the bone of the costal plate. In the 
fossil the costal plates hide the upper surfaces of the rib down to 
the edges of the peripherals. 
The nuchal of the fossil differs in a conspicuous manner from 
that of the recent C. serpentina. In the latter there is on each side 
a slender process which runs along the inner border and inferior 
face of the anterior peripherals, reaching the hinder end of the 
second peripheral. In the fossil species this process is very short, 
as shown in figure I of plate 3. On the left side of the bone this 
process is broken off; on the right it is complete. The nuchal had 
an extreme width of 70 mm.; a length of 20 mm. in the midline. 
The nuchal scute had a length of 6 mm. and a width of 24 mm. 
The width of the first vertebral scute was 52 mm.; its length on the 
midline, 38 mm. 
The first costal plate has an extreme width, fore and aft, of 
34 mm.; a length of 64 mm., not including the distal end of the rib. 
The free proximal part of the rib has about the same size as in 
C. serpentina, but there is in the fossil a considerably larger angle 
between it and the proximal part of the costal plate. This differ¬ 
ence in the direction taken by the free part of the rib is conspicuous 
in all of the costal plates. 
TRACHEMYS? NUCHOCARINATA HAY. 
This species was first recognized (8th Ann. Rep. Fla. Geol. 
Surv. p. 70, pi. VI., fig. 5) from a portion of a nuchal bone which 
had been found in Pleistocene deposits at Station 120, on the Inland 
Waterway canal, about 20 miles north of St. Augustine. A nuchal 
bone found in No. 3 at Vero evidently belongs to the same, species. 
Its catalog No. is 7011. It is complete and shows no signs of 
transportation. It is considerably smaller than the type, the length 
on the midline being only 29 mm., the greatest width 35 mm.; the 
width on the front border 14 mm. The first vertebral scute area is 
23 mm. wide and is ornamented by the ridges produced by the 
growth of the horny scute. There is a prominent median keel. 
Another nuchal No. 7573 was found in stratum No. 2. In size 
it is intermediate between the type specimen and the one described 
above. The bone is complete, and without abrasion of any kind. 
The total length in the midline is 39 mm.; the total width, 42 mm.; 
the width of the front border, 22 mm.; the width of the first verte- 
