NATURAL HIStORY OF SOUTH AFRICA 



an affection of the labyrinth of the ear ; but after a 

 careful examination of their auditory organs, Dr. K. 

 Kishi has concluded that the waltzing habit has been 

 developed owing to confinement for a great many 

 centuries in small cages in which they were obliged 

 to run in tiny circles. 



In South Africa the chief natural enemies of the 

 House Mice are snakes. Venomous snakes, of course, 

 cannot be permitted to take up their quarters un- 

 molested in dwellings and outhouses, but all snakes 

 are not venomous. There are a good many species 

 in South Africa which are quite harmless, for they 

 do not possess any vestiges of grooved fangs or 

 poison glands, and are, in consequence, as innocent 

 as lizards. One of these harmless species of snakes, 

 known as the Brown- House -Snake (Booden lineatus) 

 is generally distributed throughout South Africa and 

 Tropical Africa. A peculiarity of this snake is its 

 partiality for human habitations and their vicinity. 

 Its body is long, cylindrical and tapering, and 

 eminently adapted for pursuing mice to their most 

 secret retreats. Guided by its keen sense of smell, 

 it relentlessly hunts them down, and penetrating 

 to their nests it makes a meal of the entire family : 

 This snake feeds almost exclusively on mice and young 

 rats, and in consequence is of the utmost possible 

 economic value. However, owing to the prevailing 

 belief that all snakes are venomous, and also to the 

 general inability to recognise one species of snake 

 from another, this valuable friend is killed at sight. 



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