138 



MEMOIRS OF THE CARNEGIE MUSEUM 



narrow, but deeply notched. The length of the anterior lobe is about 100 mm.; 

 its width at the base is about 162 mm. The length is therefore only 61 per cent. 

 of the width. From the axillary notch the free border runs straight forward for a 

 short distance then curves in regularly to the epiplastral lip, which is missing in 



Fig. 15. Echmatemys obscura. Tjr[)e, C. M. No. 3252. Plastron. One-fourth natural size. 



this specimen. This free border is relatively thin and acute, thickening somewhat 

 as it approaches the lip. The lip appears to have been about 50 mm. wide. 



The entoplastron has a length of about 60 mm. and a width of 55 mm. It is 

 crossed by the humero-pectoral sulcus, and is also overlapped by the gular scutes. 

 It is pear-shaped in outline, in this respect resembling the entoplastron of Ech- 

 malemys douglassi. The bridge is 150 mm. in width. 



The length of the posterior lobe is 120 mm. Its width at the base is 191 mm. 

 The length is therefore 62 per cent, of the width. The free borders are slightly 

 contracted at the femoral-abdominal sulcus, and again at the femoral-anal sulcus; 

 from which point the border turns in rapidly toward the center. The posterior 

 lobe is terminated posteriorly by rather sharp projecting points on either side of 

 the narrow, but rather deep, median notch. It is estimated that the notch had a 

 depth of 30 mm. The posterior borders of the lobe are acute. At the center of 

 the notch the bone has a thickness of 5 mm. 



The anterior lobe curves upward toward the carapace much as in Echmatemys 



