NATURAL HISTORY OF SOUTH AFRICA 



the abundance of cover afforded ; and the profu- 

 sion of seeds which fall to the ground from the 

 acacia trees, constitute their chief diet. They do 

 not increase sufficiently, however, to become a 

 plague. 



Striped Rats are good food for a host of creatures 

 which foregather and prey upon them, and, being 

 provided with such an excellent food-supply, they 

 in turn increase rapidly in numbers. 



Thus does Nature restore the balance, when not 

 ignorantly interfered with by Man. 



In this forest the chief enemies of the Striped Rat 

 are Puff Adders, Ringhals, Mole Snakes, Mungooses, 

 Muishonds, Wild Cats and Owls. 



In more open situations the Hawk and the Secre- 

 tary Bird levy a heavy toll upon these rats. The 

 latter bird, after killing the rat with a blow of its 

 horny foot, or powerful curved beak, swallows it 

 whole. I have found as many as eight Field Rats 

 in the crop of a Secretary Bird. 



There are two distinct types of Striped Field 

 Rats. 



The chief difference between these two types is as 

 follows : 



The Field Rat {Rhahdomys pumilio typicus) and 

 its local races have four black stripes along the 

 -back, the fifth finger being normal and fairly well 

 developed. 



On the contrary, the Single-striped Rat (Lemnis- 

 comys dors alls typicus) and a local race (JLemniscotnys 



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