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. 1 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 

 t-i those of other groups of Reptiles. 



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

 -. -in od in the Collection of the Museum, the number of specimens 

 amounting to 2528. 



G. A. BOULENGER. 



Zoological Department. 

 July 28th, 1894. 



