218 FOSSIL TURTLES OF NORTH AMERICA. 
of the fragment, only 12 mm. ‘The sutures are very jagged. Nearer one sutural border a 
sulcus descends, which separated two costal scutes. Two other costals measure each 72 mm. in 
width at the distal end. In all these the free end of the rib projected beyond the distal border. 
A nuchal is represented by the greater part including the entire front. There was an 
articular tuberosity for the eighth conical: the anterior border of this bone was 200 mm. 
long. It is excavated somew hat for the neck and head. The upper surface is quite convex 
from side to side. Antero-posteriorly the bone measures g6mm. ‘The front border is obtuse; 
behind it a short distance the thickness is 16 mm., increasing at the ends of the bone to 20 mm. 
The hinder border joined suturally the first costal bone. 
The first left peripheral is connected with the nuchal. It is 110 mm. long and 80 mm. 
wide. The hinder border articulated with the first costal. The free border is obtuse and the 
distal end is 18 mm. thick. There is present the proximal end of another left first peripheral 
which is considerably thicker than the one just described. 
What are evidently right and left second peripherals, of an individual smaller than either 
of the above, are present. The proximal end of the one of the left side is 65 mm. wide, whereas 
the distal end of the left first, described above, is 72 mm. wide; besides, the two do not fit 
Fics. 275-280.—Procol pochelys grandeva. Various peripherals. X32. 
/) Beli? 3 
275. Section across middle of supposed second peripheral; free border toward 
right. No. 1027 A.M.N.H. 
6. Section at anterior end of second peripheral. Princeton Univ. Coll. 
7. Section near hinder end of third peripheral. Princeton Univ. Coll. 
. Section near front end of supposed fifth peripheral. Princeton Uniy. Coll. 
g. Right hinder peripheral, view above. Princeton Univ. Coll. 
o. Upper surface of supposed eleventh peripheral. Princeton Univ. Coll. 
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together as they should if they belonged to the same oe No differences are seen 
that indicate different species. This second peripheral (fig. 276) is 95 mm. long, 64 mm. 
wide and 22 mm. thick proximally; 51 mm. wide and 25 mm. thick distally. The anterior 
border is obtuse, the hinder acute and with suture for a costal. The succeeding, or third, 
peripherals are joined to those just described. They measure about 95 mm. along the free 
border and are 70 mm. wide at the distal end. A ridge that begins on the inferior surface of 
the second becomes more conspicuous near the outer border of the anterior half of the third; 
and just above it, near the front of the bone, is the pit for the rib of the first costal. Fig. 277 
is a section at the hinder end of this peripheral. 
There are present nineteen peripherals, not counting the part of a first which belongs to 
the larger individual. At least three are not at all represented; but at least two that are 
