CLASSIFICATION OF CHELONIA. 



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of compartments into which branches of the bronchus open. There is 

 a slight muscular " diaphragm." The filling and emptying of the lungs 

 is helped by the protrusion and retraction of the head and legs, but 

 there are also " swallowing movements." There are no vocal chords, 

 but there is sometimes a feeble voice. 



In the maJes, the kidney, the epididymis, and the testes lie adjacent 



FIG. 334. Scales on ventral surface of plastron of 

 Greek tortoise. 



G., Gular ; .//., humeral; P., pectoral; Ah., abdominal; 

 f. t femoral ; A. t anal; M., marginal. 



to one another on each side. The males have a grooved penis attached 

 to the anterior wall of the cloaca. There is a urinary bladder. 



Classification of Chelonia 



I. ATHEC/K. Vertebrae and ribs free from carapace. Skull 

 without descending processes from parietals. 



Sphargidse, leathery-skinned turtles, with flexible carapace. Sphargis 

 (Dermatochelys) coriacea, the only living species, the largest modern 



