CHELONTDJE. 



43 



very well, the premaxillae being entire. The arrangement 

 of the shields is the same as in the type ; but the length 

 of the symphysis (as in No. 32386) is relatively longer. 



Bowerbank Collection. Purchased, 1865. 



Fig. 10. 



pitvai 



Argillochelys antiqua. — Frontal aspect of the cranium and ventral aspect of the 

 mandible ; from the London Clay of Sheppey. \. pmx, premaxilla ; 

 mx, maxilla ; qj, quadratojugal ; prf, prefrontal;^, frontal; ptf, post- 

 frontal ; par, parietal. The sharp lines indicate the boundaries of the 

 epidermal shields, of which the names are given in fig. 11 ; the occipital 

 shield is confluent with the interparietal. 



37213. A smaller cranium ; from Sheppey. The greater part of 

 the palate is concealed by matrix ; but the palatal ridges 

 separated by a median groove are visible, and correspond 

 in general characters with those of A. cuneiceps. 



Bowerbaiik Collection. 



R. 1364. A skull agreeing in size with the preceding, and probably 

 belonging to the same species; from the Red Crag of 

 Suffolk, and derived from the London Clay. Most of the 

 outer bones have been removed, leaving a hard cast of the 

 hollows of the skull. 



Harford Collection. Purchased, 1888. 



R. 1364 a. A larger skull in a similar condition, probably belonging 

 either to this or the next species ; from the Red Crag. 



Harford Collection. 



