78 BBCKONID^, 



II. Back with uniform lepidosis. 



A. Digital expansions well developed. 



1. Dorsal scales not larger than those on the snout. 

 a. Dorsal scales not keeled. 



a. Digital expansion considerably wider than the digit. 

 * Mental not twice as broad as long. 



Eostral four-sided, entering considerably 



the nostril; first labial not entering 



the nostril 14. porphyrews, p. 87. 



Eostral pentagonal or hexagonal, the 



latero-snperior border entering the 



nostril; first labial entering the nostril; 



digital expansion much smaller than 



the eye ; 7 or 8 entire lameUse under 



the fourth toe 15. marmoratiis, p. 88. 



Digital expansion large, that of the fourth 



toe measuring nearly the diameter of 



the eye ; ear-opening minute 16. macrodactylus, p. 89. 



Rostral separated from the nostril; 10 



entire lamellae under the fourth toe . . 17. ctffinis, p. 89. 



10 or 11 entire lamellae under the fourth 

 toe; ear-opening large, oval, measuring 

 two thirds or three fourths the diameter 



of the eye 18. guentheri, p. 90. 



** Mental twice as broad as long. 



Scales on the snout not larger than those 



on the back 19. europceus, p. 90. 



ji. Digital expansion scarcely wider than the digit. 



The scales on the upper surface of the 

 head much larger than the granules 

 on the back 20. pictus, p. 91. 



Dorsal scales flat, as large as those on 

 the snout; two median larger chin- 

 shields 21. lineatus, p. 92. 



b. Dorsal scales feebly keeled. 



The scales on the back about as large as 



those on the snout 22. ocellatus, p. 93. 



2. Dorsal scales larger than those on the snout. 

 7 upper and 6 lower labials 23. unctus, p. 94. 



11 upper and 10 lower labials 24. riebeckii, p. 94. 



B. Digital expansion extremely small. 

 Digits slender 25. gerrhopygus, 95. 



