31-2 



4- Fam. Dermochelyidae. 



Shell without epidermal shields; vertebrae and ribs free, 

 separated from the bony exoskeleton, which consists of mosaic- 

 like juxtaposed plates. Neck incompletely retractile; ear hidden. 

 Plastron reduced; eight plastral bones, no entoplastron. Limbs 

 paddle-shaped, without claws. 



Marine. 



A single genus. 



I. Dermochelys Blainv. 

 (Blainville, Journ. de Phys. LXXXIII p. 259, 1816). 



Head covered with small horny shields, which disappear 

 with age; upper jaw in the middle with two triangular points 



Fig. 119. Dermochelys coriacca (L.). Young specimen, nat. size. 



between three deep notches; jaws sharply edged, alveolar 

 region not enlarged. Dorsal shield with seven, ventral shield 

 with five keels. Limbs paddle-shaped, without claws. 



