19. CHELONIIDJE 



eggs are spherical and very numerous, are inclosed in leathery 

 shells, and when deposited in the pits are covered with sand 

 and left by the turtle. 



Our knowledge of sea turtles is still too limited to justi- 

 fy any very definite conclusions as to the number of species, 

 or even very emphatic statements as to the difference or iden- 

 tity of Atlantic and Pacific Ocean specimens. Still it seems 

 best to regard those from the Pacific as distinct species. 



Synopsis of Genera 

 a. — Carapace covered with thicker, horny, imbricate shields; 

 pectorals and abdominals usually keeled; two pairs of 

 prefrontal shields; costals four. 



Eretmochelys. — p. 99+. 

 a. — Carapace covered with thin, juxtaposed, shields; pector- 

 als and abdominals usually smooth, 

 b. — Vertebral plates five; costals four; one pair of pre- 

 frontal shields. 



Chelonia. — p. 996. 

 b'. — Vertebral plates usually more than five or costals more 

 than four; two pairs of prefrontal shields. 

 Caretta.— p. 998. 



Genus 55. Eretmochelys 



EretmocAelys Fitzinger, Syst. Rept., 1843, p. 30 (type, imbricata) . 

 Onychochelys Gray, Proc. Zool. Soc. Lond., 1873, p. 397, (type,0. 

 kr^ussi). 



Shell covered with thick, imbricate, horny plates, the 

 tortoise shell of commerce. Two pairs of prefrontal plates. 

 Limbs large, paddle-shaped, with two claws. The verte- 

 bral and costal plates are keeled in young, and the plastral 

 plates in adults also. The marginals project making the edge 

 of the carapace serrate. The beak is hooked like that of a 

 hawk. 



