2l8 



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 cervical; the anterior border of this bone was 200 mm. 

 long. It is excavated somewhat for the neck and head. The upper surface is quite convex 

 from side to side. Antero-posteriorly the bone measures 96 mm. 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 1 10 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 



FIGS. 275-280. Procolpochelys grandeeva. Various peripherals. 



275. Section across middle of supposed second peripheral ; free border toward 



right. No. 1027 A.M.N.H. 



276. Section at anterior end of second peripheral. Princeton Univ. Coll. 



277. Section near hinder end of third peripheral. Princeton Univ. Coll. 



278. Section near front end of supposed fifth peripheral. Princeton Univ. Coll. 



279. Right hinder peripheral, view above. Princeton Univ. Coll. 



280. Upper surface of supposed eleventh peripheral. Princeton Univ. Coll. 



together as they should if they belonged to the same individual. 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 



