xii THE SNAKES OF SOUTH AFRICA. 



species differ materially in coloration and length in the different 

 parts of South Africa, especially so where climatic and other 

 conditions are largely dissimilar. 



The Author and Publisher both wish to acknowledge gratefully 

 their obligations to the following : The British Museum (Natural 

 History) Authorities for the use of a few illustrations from the 

 British Museum Catalogue of Snakes, also for Dr. Boulenger's 

 classification list of Snakes from the same source ; Messrs. Blackie 

 for the use of certain illustrations from their Physiology ; Sir Ray 

 Lankester and Messrs. Constable and Company, Ltd., London ; 

 Messrs. F. W. Warne & Co., for kindly allowing the use of 

 illustrations from their " Royal Natural History " ; Messrs. 

 Funk & Wagnall for diagrams ; Messrs. Harmsworth ; Prof. 

 Seeley for his pictures " Dragons of the Air " ; also Messrs. 

 Harmsworth, for illustrations from their "Natural History," 

 and "Cliildren's Encyclopaedia." 



