GENERAL NOTES ON SNAKES. 



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FlG. 347. Skull of grass-snake. From W. K. Parker. 



A, Dorsal surface p x. , premaxilla ; mx., maxilla ; an., external nostril ; ., nasal ; ol., 

 nasal cartilages ; pf., prefronto-lachrymal ; p., parietal ; 7., frontal ; pa., palatine ; 

 t.pa., transpalatine ; pg., pterygoid ; pro., pro-otic; ep., epiotic; op., opisthotic ; 

 so., supraoccipital ; eo., exoccipital ; ar., articular ; s.ag., surangular ; ag., angular ; 

 d. , dentary ; q., quadrate; sq. , squamosal. B, Ventral surface PX., premaxilla; ol., 

 nasal cartilage; mx., maxilla ; v., vomer;/.j palatine ;^., parasphenoid;./:, frontal ; 



