CHARACTERS OF CHELONlA 



pace^ for this must tend to make respiratioji less active, 

 lungs are divided into a number of compartments . 



687 

 The 



Fig. 397. — External appearance of tortoise. 



pnx 



Fig. 398.— Skull of turtle. 



S.O., Supra-occipital; PAR., parietal; FR., frontal; P.F., pre- 

 frontal ; PO.F., post-frontal ; SQ., squamosal ; PMX., pre- 

 maxilla ; MX., maxilla ; /., jugal ; Q.J., quadrato-jugal ; Q., 

 quadrate; D., dentary ; ^A^., angular; AR., articular; S., 

 surangular. 



The cloacal aperture is usually longitudinal, never trans- 

 verse ; the copulatory organ is unpaired. 



All are oviparous. The eggs have firm, usually calcareous, 

 shells. 



