No. 1747. DESCRIPTIONS OF VEW FOSSIL TURTLES HAY. 323 



jagged suture with the hyoplastron. The remainder of the lower 

 border of the sixth and the whole of the same border of the seventh 

 peripherals were similarly joined to the hypoplastron. The eighth 

 (figs. 22, 23) has a pit in the inner face of its anterior end for a process 

 of the hypoplastron. The anterior end of the eighth is 18 nun. 

 thick, the posterior end 12 mm. The ninth peripheral (fig. 23) is 

 27 mm. high, and it has a, pit near the hinder end of its upper border. 

 The tenth peripheral dig. 23) seems to have had a. pit for the rib of 

 the last costal plate. There is another peripheral (fig. 23) which 

 appears to be the eleventh of the left side. It, presents no pit in its 

 upper border. Its border for the pygal is '.) mm. thick. The upper 

 border of the third peripheral of the left side indicates that it joined 

 the second costal by a jagged suture, and the same sort of union is 

 betrayed by the distal end of what appears to be the second costal. 

 The distal end of the fourth costal was evidently similarly sutured 

 to the sixth peripheral. It is probable that all of the costals above 

 the bridges were closely joined to the corresponding peripherals. 

 The ninth peripheral has the upper border thin and smooth; the 

 eleventh has this border jagged. From the somewhat upturned free 

 border of the third peripheral a low keel, bounded above by a groove, 

 is continued backward on the bridge peripherals, descending again 

 to the free border of the eighth and succeeding peripherals. 



Of the plastron there are missing the left epiplastron, the outer 

 extremity of the left hypoplastron, the whole of the right xiphiplastron, 

 and the hinder end of the left xiphiplastron. The form of the plasl ron 

 and of its various bones is shown by the figure (Plate 12, fig. 2) 

 The total length of the plastron was close to 130 mm. The anterior 

 lobe is 40 mm. long and 70 mm. wide at the base. The free border 

 is obtuse and about 5 mm. thick. There is. no suggestion of an 

 epiplastral lip. The entoplastron is 26 mm. long, 20 mm. wide, !> 

 mm. thick, pointed in front and broadly rounded behind. The 

 hypoplastra joined a distance of 25 mm. on the midline; the hypo- 

 plastrals, 20 mm.; the xiphiplast rals probably about 40 mm. The 

 hinder lobe was (dose to 48 mm. long and 55 mm. wide at the base. 

 The greatest thickness of the hypoplastra is 14 mm.; of the xiphi- 

 plast ra, !) mm. 



The sulci of the carapace are narrow, but deeply impressed. The 

 sulci descending on the second, fourth, and sixth costal bones are 

 nearer the hinder border of the bones. The second vertebral scute 

 was evidently .'if mm. wide. The third was 36 mm. wide and about 

 r> mm. long. The costo-marginal sulci run along just below the 

 upper borders of most of the peripherals, descending on (he hinder 

 peripherals to about the middle of their height. The int ermargiiial 

 sulci descend a little in front of the middle of the length of the 

 peripherals. 



