PREFACE 



from attempting a general account of them. Moreover, the 

 number of species of recent lizards and snakes is so bewilder- 

 ing, the genera of many families being but tedious variations of 

 the same theme, that only those forms have been described 

 which are the most important, the most striking, or which the 

 traveller is most likely to come across. The student who wishes 

 to go farther into systematic details must consult the seven 

 volumes of the Gatalogiie of Reptiles in the British Museum 

 (London, 1889-1896). Mr. G. A. Boulenger, the author of this 

 magnificent series, has rendered the systematic treatment of 

 recent Amphibia and Eeptiles an easy task. During many 

 years of the most friendly intercourse I have profited on count- 

 less occasions by his ever -ready advice. Although he has 

 kindly read the proofs of the part dealing with the Amphibia 

 it would be unfair to associate him with any of its short- 

 comings or- with contestable opinions, for which I alone am 

 responsible. 



Cope's large work on the Crocodilians, Lizards, and Snakes 

 of North America {Rep. U.S. Nat. Mus. for 1898 (1900)) has 

 unfortunately appeared too late to be used in the present 

 work. 



The drawings on wood were, with few exceptions, made by 

 Miss M. E. Durham, mostly from living specimens — a procedure 

 which has to a gi'eat extent determined the selection of the 

 illustrations. 



Since both the metric and the English systems of measure- 

 ments have been employed, it may be well to state for the 

 convenience of the reader that the length of a line of the text is 

 four inches or approximately ten centimeters. 



I have frequently and freely quoted accounts of previous 

 authors instead of paraphrasing them. Especial thanks are due 

 to Messrs. Longmans, Green, and Co., and to Messrs. Murray, 



