INTRODUCTION. 



In dealing with the multitude of forms of Aglyphodont Colubroids, 

 all of comparatively simple structure, the lack of prominent cha- 

 racters on which to establish genera is seriously felt, and, but for 

 the study of the dentition, satisfactory definitions could not be 

 drawn up. I have therefore, as in the previous volume, supplied 

 numerous outline-figures of jaws to facilitate the understanding of 

 the diagnoses. 



I have endeavoured to avoid both extremes of excessive fusion or 

 separation in my attempt to render genera approximately equivalent 

 to those of other groups of Eeptiles. 



Descriptions of 427 species are given. Of these, 347 are repre- 

 sented in the Collection of the Museum, the number of specimens 

 amounting to 2528. 



G. A. BOULENGER. 



Zoological Department, 

 .July 28th, 1894. 



