338 THE REDISCOVERED COUNTRY 



not disturbed, my eye caught first the topi, second the harte- 

 beeste, and lastly the zebra. The reason for the com- 

 parative invisibiHty of the latter belongs under a different 

 head. 



In a letter to me Colonel Roosevelt takes the position 

 that if such a tendency exists, ''even to the extent that 

 would represent the killing of say a hundred topi by lions' 

 for every ninety-nine hartebeeste. . . . If it exists in 

 the locahty you mention, the fact will be proved by the 

 speedy extermination of the topi in that locality." And he 

 calls to my attention the indisputable fact that both beasts 

 are well known, possess equal fecundity, equal wariness, etc. 

 I am not quite willing to admit this. The fecundity and 

 infant mortality of different animals in different localities 

 have not yet been studied. That breeding is affected by 

 conditions is indisputable. Before a drought season Cali- 

 fornia quail will raise one brood — or none; in seasons of 

 plenty they may raise three broods. If this is true, it may 

 well be that in a locality better adapted to topi than to 

 kongoni the former may breed more freely than the latter; 

 so freely as to more than compensate for lion killing. It 

 seemed to me that, in this new country, I saw many more 

 young topi than young kongoni, and more twins of the 

 former than of the latter; but this is only an impression. 

 Certainly if some such explanation is not adopted, it would 

 be very difficult to account for the fact that in different 

 localities species practically aHke in habits differ so widely 

 in their relative numbers. On the plains north of the Nar- 

 ossara River the kongoni outnumber the topi by about ten 

 to one; on the plains south of the Mara River the exact 



