652 



Bulletin American Museum of Natural History 



[Vol. XLVI 



calated row of small subdigital scales between the fringe and the sub- 

 digital lamellae proper. The accompanying figures illustrate these char- 

 acters of the digits in Uma notata, Callisaurus crinitus and Callisaurus 

 ventralis. It seems evident that crinitus is much more closely allied to 

 ventralis than to Uma notata, and that the development of the fringe has 

 been independent in the two forms. 



E 



G 



B 



Fig. 7. .4 and B, ventral'and posterior lateral views of the base of the fourth toe of Callisaurus 

 ventralis ventralis (A. M. N. H. No. 2454). C and D, same of Callisaurus crinitus (U. S. N. M. No. 64530) 

 E and F, same of Uma notata, Field Mus. No. 1203. G, posterior lateral surface of foot between base 

 of fourth and fifth toes, showing extension of the fringe scales and transition to smooth scales of same 

 specimen. //, distal joint of third toe, showing narrowness of the ventral lamella? and insertion of a 

 double row of small scales between them and the fringe scales, same specimen. All X 0.6. 



Key to the Species of Callisaurus and Uma 



Digits with or without a lateral fringe; subdigital scales broad, in a single row; 

 coloration not ocellated Callisaurus. — 2. 



Digits with a long lateral fringe; subdigital scales in more than one row; dorsal 

 coloration ocellated. (A single species, Uma notata; deserts of southern 

 California 'and adjacent parts of Arizona.) Uma. 



