52 CHELONIA. 



tortoises are separate ; the sternum is covered with 6 pairs 

 and a small intergular plate placed before or between the 

 gular pair. The sterno-costal suture is covered with a series 

 of 4 nearly square plates on each side, the places of which in 

 the other tortoises are occupied by the outer end of the pec- 

 toral and abdominal plates. There are several large axillary 

 and small inguinal plates at the ends. 



The head is covered with regular shields, and Prof. Gra- 

 venhorst has used the cheek- shields as a specific character. 



The number of claws has also been used as a specific cha- 

 racter in these tortoises, but they are very apt to vary, and 

 are often different on the two sides of the same animal. 



Merrem has used the name of Caretta for this genus. 



1. Chelonia imhricata, [Imhricatecl Turtle.) Testa elliptica 

 declivi carinata, scutellis disci imbricatis luteo fusco variegatis. 



Testudo imhricatus, Lin. Chelonia imhricata, Schw. Imbri- 

 cated Turtle, Shaw. Caretta imhricata, Merrem, Lacep. H. 

 Q. O., t. 1, f. 2, cop. E. M. t. 4, f. 1.— Grew, Rar. t. 3.— 

 Schoepf, t. 18, f. a. cop. Daud, t. 17, f. 2, and Shaw, Zool. t. 

 26.— Schoepf, t. 18, B.— Seba. t. 80, f. 9. Shaw Zool. t. 27. 



Junior. Scutellis disci subimbricatis, postice truncatis. 

 Caretta nasicornis, Merrem, Schoepf, t. 17, f. 1- 



Habitat in Oceano Americano et Indico, (v. Mus. Brit, 

 et Bell.) 



Schoepf describes the sternal plates as 12 ; the specimen 

 in the British Museum has 13, like all the other Chelo?iia'; 

 the upper jaw is said to be hooked and entire. 



Chelonia multiscutata, Kuhl, Beitr. 78, with 25 (9 verte- 

 bral and 1 6 costal) keeled imbricate dorsal shields, may be a 

 monstrosity of this species. 



2. Chelonia My das, ( Gieen Turtle.) — Testa cordata declivi 

 carinata, scutellis disci planis inermibus ; maxilla inferiore 

 profunde serrata. 



Test. My das, Lin. S. N. Lacep. 20, t. 1, f. 1, cop. E.M. t. 

 3, f. 2. Daud. Rept. t. 16, f. 1. Shaw Zool. t. 20, Anat., 

 Schoepf. t. 17, f, 1. (Jun.) Cuv. Os. Fos. v. t. 11, f. 1, 4. 

 t. 13, f. 6, Spix, Cephal. t. 1,2, f. 5, (Anat.) 



a. Testa unicolore, scutellis vertebralibus regularibus hexa- 

 gonis. Test, viridis, Schn. Chelonia Mydas, Schw. 



j3. maculosa, scutellis luteis nigro maculatis, vertebralibus 

 duplo longioribus quam latis. Test, maculosa, Cuv. R. A. 

 ii. 15. 



