OLIVE WATER SNAKE. 



91 



Colour — The colouration varies considerably according to the locality of 

 the species — 



A. Vertebral spots elongate and more or less confluent into a zig-zag 



vertebral band ; a black stripe along upper surface of tail ; 

 under-parts spotted with blackish. 



B. A dorsal series of large squarish or rhomboidal dark spots, sepa- 



rated by Hght intervals, alternating with a lateral series of spots 

 or cross bars ; under-parts spotted or dotted only at the sides. 



C. Pale reddish-brown above with the markings very much effaced. 



Intermediate between B. and F. 



D. Dorsal markings as in B. but ventrals edged with blackish. 



E. Dorsal spots confluent with lateral ones, forming cross bands ; 



belly unspotted. 



F. No spots or markings of any kind (Natal). 

 Average length — 3 feet. 



Distribution — Generally distributed over South Africa ; ranges as far 

 north as Sennar and Sierra Leone. 



. ^^ 



Fig. 40. — Brown House .Snakes hatching 



Olive Water Snake. 



{AblabopMs rufulus.) 



This well-known snake is common in suitable localities all 

 over South Africa. It is invariably found in the neighbourhood 

 of swamps, vleis, and the banks of rivers and pools. It is an expert 

 swimmer and diver, as well as climber. In captivity it prefers 

 frogs to any other food, showing great expertness in their capture. 

 I have, on several occasions, observed these Olive Water Snakes 

 chase frogs into the water and dive down and secure them at the 



