VI INTRODUCTION. 



any particular region, biit give the highest number to be found at 

 any point between the anterior and the posterior fourth of the body. 

 The indication of the number of teeth refers to the full set in each 

 maxillary ; few specimens show the complete dentition, gaps oc- 

 curring here and there, but shallow sockets in the bone indicate 

 the bases of the missing teeth. The figures intercalated in the text 

 will help to make clear the dental characters employed in diagnosing 

 the genera. A figure of the skull, with all the bones lettered, 

 accompanies the definition of every family. 



The dimensions are taken from the largest specimens in the 

 Collection. 



As in the preceding Catalogues of Reptiles and Batrachians, the 

 letters in square brackets in the third column of the list of specimens 

 signify :— " [P.] " = " Presented by " ; " [C] " = " Collected by " ; 

 " [E.] " = " Obtained by exchange." 



G. A. BOTJLENGEH. 



Zoological Department, 

 January 23rd, 1893. 



