50 ' SPHABGID^. 



46. Thalassoclielys caretta. 



Testudo caretta, Linn. Syst. Nat. \, p. 351. 



Chelonia caoiiamia, Schwcifff/. Prodr. p. 22, 



Clielonia olivacea, Eschsch. Zool. Atl. p. 3, pi. iii ; Cantor, J. A. S. B. 



xvi, 1847, p. G19. 

 Caouana olivacea, Giinth. Rept. B. I. p. 52 ; Theoh. Cat. p. 33. 

 Thalassochelys caretta, Bouleng. Cat. Chel. 8^c. p. 184. 



Carapace of young with three strong keels, of adult arched or 

 subtectiform ; dorsal shields juxtaposed ; margin serrated pos- 

 teriorly in the young, formed of 27, or rarely 25 shields. Intergular 

 shield very small or absent. Head large, with very strong, hooked 

 jaws ; symphysis of lower jaw very long ; alveolar surface of horny 

 beak with a median ridge, of jaws without ; two pairs of shields 

 anterior to the azygous frontal. Limbs of young usually ^^■ith two 

 claws, of adult frequently with but one. Toinig uniform dark 

 brown or blackish ; adult brown above, yellowish inferiorly. 



Length of shell 4 feet. 



Hah. Tropical and subtropical seas ; Mediterranean ; an acci- 

 dental visitor in the North. Not rare in the Bay of Bengal. 

 Carnivorous, feeding chiefly on crustaceans and mollusca. 



Suborder II. ATHEC^. 



Family V. SPHARGID^. 



Exoskeleton consisting of mosaic-like juxtaposed plates. Plastral 

 elements eight ; no entoplastron. Limbs paddle-shaped, cla\\'less, 

 the digits of the fore limb much elongate ; phalanges without 

 condyles. 



This family contains a single genus and species, the well-known 

 Leathery Turtle. 



Genus DERMOCHELYS, 



Blainville, Journ. de Phys. Ixxxiii, 1816, p. 259. 



Dorsal shield completely, ventral shield incompletely bony in the 

 adult, the former w ith seven, the latter with five keels. Beak with 

 two triangular cusps, between three deep notches ; no enlarged 

 alveolar surface, the jaws simply sharp-edged. Head covered with 

 small shields. 



47. Derniochelys coriacea. 



Testudo coriacea, Linn. Sy!<t. Nat. i, p. 350. 



Spliargis coiiacea, Gray, Si/n. Rept. i, p. 51. 



Dermatochelys coriacea, Giinth. Rept. B.I. p . 55 ; Theoh. Cat. p. 34. 



Dermoclielvs coriacea. Bunlentj. Cat. Chel. ^-c. p. 10. 



Eore limbs as long as the dorsal shield in the young, shorter in 

 the adult. Colour dark brown, uniform or spotted with yellow ; 



