1«(> 



lion of the second sub marginal scute area willi an internal projecting angle 

 intermediate in extent to that of the former specimens. On one side, also, a 

 small portion of the first submarginal area is retained, and this appears to 

 indicate that it was nearly of the size and shape of that in the first-described 

 specimen of Baena. 



Comparative measurements of the three described specimens of Bacna 

 arenosa are as follows : 



Length of first vertebral scute at middle 



Breadth of flrst vertebral scute at middle . . . 

 Length of second vertebral scute at middle. . 

 Breadth of second vertebral scute at middle . 

 Length of third vertebral scute at middle . . . 

 Breadth of third vertebral scute at middle. . . 

 Length of fourth vertebral scute at middle . . 

 Breadth of fourth vertebral scute at middle . 

 Length of fifth vertebral scute at middle 



Breadth of fifth vertebral scute at middle 



Width of first costal scute internally ' 



Width of second costal scute internally ~ 



Width of third costal scute internally 



Width of fourth costal scute internally 



Length of anterior prolongation of the plastron 



Breadth at base of anterior prolongation of the plastron . . 



Length of posterior prolongation of the plastron 



Breadth at base of posterior prolongation of the plastron . 



Breadth of pedicles of plastron 



Length approximately of pedicles of plastron 



Length of gular scutes internally 



Breadth of gular scutes at back border 



Length of humeral scutes internally 



Breadth of humeral scutes at back border 



Length of pectoral scutes internally 



Breadth of pectoral scutes at middle 



Breadth of pectoral scutes at back border 



Length of abdominal scutes internally ... , 



Breadth of abdominal scutes at middle 



Breadth of abdominal scutes at back border 



Length of femoral scutes internally 



Breadth of femoral scutes at back border 



Length of caudal scutes internally 



Fore and aft diameter of first scute of pedicle 



Fore and aft diameter of second scute of pedicle 



Fore and aft diameter of third scute of pedicle. 



Lines, j Lines. 



16 

 20 

 Fore and aft diameter of fourth scute of pedicle 22 



36 

 36 

 35 

 37 

 29 

 37 

 32 

 48 



37 

 32 

 21 



46 

 48 

 50 

 62 

 26 



24 

 32 

 41 

 31 

 15 

 41 

 34 

 28 

 21 

 21 



22 

 36 

 35 

 30 

 35 

 31 

 28 

 30 

 26 

 40 

 34 

 30 

 30 

 17 

 35 

 41 

 48 

 52 

 58 

 24 

 10 

 14 

 26 

 19 

 24 

 45 

 31 

 22 

 3S 

 29 

 26 

 22 

 22 

 18 



24 



20 



Lines. 



35 

 32 



34 

 32 



33 



38 

 30 



37 

 44 



52 

 56 

 24 

 16 

 15 

 21 

 22 

 22 

 50 

 33 

 20 

 44 

 28 

 24 

 19 



