82 THE GROWTH OF GROUPS 



This account of the white-bellied rats in India may 

 be closed with a description of the fate of the group in 

 Poona. The facts were ascertained by Captain Kundart, 

 I. M.S., to whom I am much indebted. The existence 

 of the group was made known between the months of 

 May, 1908 and 1909. At the time of my visit to Poona, 

 in February, 1909, the presence of the group in the parti- 

 cular houses was already known ; traps were set on that 

 occasion, with the result that three more white-bellied 

 rats were caught in the same houses. In February, 1911, 

 the group was again sought for. Between the 2nd and 

 nth of that month, two hundred traps were set in the 

 same houses at night ; seventy- two rats were caught in 

 all, but only one of them was white bellied, the others 

 were whole coloured. Hence in less than two years the 

 group had almost died out. No doubt this is the usual 

 fate of such groups, unless they are isolated by some 

 means, but it would be a gratuitous assumption to say 

 that it is their invariable fate. The method of origin 

 of the white-bellied kind from the others seems plain 

 enough, and wherever we find this kind persisting, as, 

 for example, at Tellicherri, we should account for their 

 origin by that method rather than by a method which 

 has never been demonstrated. 



