vi INTRODUCTION, 
any particular region, but 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. BOULENGER. 
Zoological Department, 
January 23rd, 1893, 
