LIZARDS. 15 



Synopsis of the Genera. 



I. Throat ivith 2 cross folds^ ivith larger 6-sided scales hetween. 

 A. Ventral shields small, lony, smooth. Tongue contractile. 



1. Teius. Toes 5-5. Femoral pores disliuct. 



2. Callopistes. Femoral pores none. Toes 5-5. 



B. Ventral shields broad, smooth. 

 * Tongue elongate, sheathed at the base. Teeth compressed. 



3. Ameiva. Toes 5-d. Teeth 3-lobed. 



** Tongue not sheathed, free at the base. 



4. Cnemidophorus. Teeth compressed longitudinally, 3-lobed. 

 Toes 5-5. 



5. DiCRODON. Teeth compressed transversely, bifid. Toes 5-5. 



6. AcRANTUs. Teeth compressed transversely, bifid. Toes 5-4. 



II. Throat with a collar of large shields. 

 a. Collar and ventral shields keeled. Tail round. 



7. AcANTHOPYGA. Scalcs of back large, of sides granular. 



8. Centropyx. Scales of back and sides moderate, in many series. 



b. Collar and ventral shields smooth, elongate. Tail round. 



9. Emminia. Scales of back rhombic, keeled, equal. 



c. Collar and ventral shields smooth, elongate. Tail compressed. 



10. Crocodilurus. Scales of back equal, similar. 



11. CusTA. Scales of back unequal. Throat with a collar of large 

 scales. 



12. Ada, Scales of back unequal. Throat with 2 plaits. 



c 2 



