ART. 10 THE EXTINCT TURTLE TRACHEMYS SCULPTA — GILMORE 



almost entirely around the circumference of the carapace. The 

 peripheral surfaces are ornamented with coarse ridges the trend of 

 direction varying with their position on the shell. In the anterior 

 ones these ridges have a diagonal trend away from the center of the 

 carapace becoming parallel with the length of the shell on the third 

 and continuing so to the sulcus on peripheral seven. In the succeed- 

 ing peripherals the area in front of the sulcus the ridging is at right 

 angles to the free border, while posterior to the sulcus the diagonal 

 trend continues. The under surface of the plastron is without dis- 

 tinctive ornamenta- 

 tion, only a slight 

 roughening of the hyo- 

 and hypopl astral areas. 



The nuchal has a 

 length of 56 mm., a 

 width in front of 24 

 mm. and a maximum 

 width of 63 mm. These 

 same measurements of 

 the type, taken in the 

 same order, are 55 mm., 

 29 mm., and 63 mm., 

 respectively. The 

 anterior edge is obtuse 

 and slightly notched on 

 either side of the nuchal 

 scute. 



The form and pro- 

 portions of the neurals 

 are clearly shown in 

 Figure 1. Their di- 

 mensions are given in 



+1> + Kl Figure 1.— Carapace of Trachemys sculpta Hat. Cat. No. 



tne table. 11839^ U.S.N.M. nearly One-third natural Size 



Element 



Length 



Width 



Neural 1 __ 



Millimeters 

 34.0 

 26.0 

 30.0 

 27. 

 28.0 

 18.7 



15. 

 16.0 



16. 7 

 24.0 



Millimeters 

 19. 5 



2 _ 



22.0 



3 - 



22.7 



4 _ .... 



27. 7 



5 



30. 



6 



25.0 



7 -_ 



21.0 



8 _ - _ _ -. ._ _ _ 



20. 



Suprapvgal 1 __ __ 



20. 



2 __ 



45.0 







