24 SECKOKlDiE. 



belly ; the hind limb stretched for- 

 wards reaches constriction of neck. 5. Jcachhensis, p. 29. 

 Dorsal tubercles small, irregularly 

 arranged; about 25 scales across 

 the middle of the belly ; no granules 

 or small scales between the keeled 

 scales of the upper surface of the 

 tail 7. elongattis, p. 30. 



2. Infracaudal scales keeled. 

 The fore limb stretched forwards 



reaches the tip of the snout 6. heterocercus, p. 30. 



The fore limb does not reach the tip 



of the snout 8. fasciaius, p. 31. 



B. Stone- or Sand-Geckos with long slender digits and the 

 dorsal scales uniform or intermixed with slightly enlarged 

 smooth tubercles. 



1. Dorsal scales juxtaposed. 



a. Enlarged tubercles on the back or on the tail. 



Tail swollen, with enlarged tubercles. 9. stoliczJcce, p. 31. 



Tail without enlarged tubercles ; men- 

 tal plate large 10. lawderanus, p. 32. 



Tail without enlarged tubercles ; men- 

 tal scarcely larger than the adjacent 

 labials 11. dorbignyi, p. 33. 



h. No enlarged tubercles either on the back or on the tail. 



Tail cylindrical 12. mauritanicus, p. 33. 



Tail depressed ; border of the eyelid 



with prominent spine-like scales . . 13. trachyhlepharus, p. 34. 



2. Dorsal scales imbricate, like the 



ventrals 14. steudneri, p. 34. 



C. Tree-Geckos, with uniform or heterogeneous dorsal scales ; 

 clawed phalanges strong. 



1. No lateral fold. 



a. Dorsal tubercles smooth or unicarinate. 



a. Ventral scales small. 



Dorsal scales very small, granular, uni- 

 form or intermixed with very small 

 tubercles 15. nebulosus, p. 34. 



Dorsal scales very large and flat, smooth, 

 squarish, uniform ; seven lower 

 labials 16. jtyporensis, p. 30. 



