174 SPOLIA ZEYLANICA. 
It is pleasant to think that it probably lies within the power 
of man to control the conditions and reclaim the lost fertility. 
But Nature might reclaim it herself, and one wonders whether 
she has not already done so once. The well-defined line of 
demarcation between the two sets of deposits exposed along 
the scarp points to a discontinuity in the sequence of events. 
Thus, the question arises, Does the upper limit of the lower beds 
represent the buried surface of an ancient desert plateau or not ? 
It is impossible to answer this question definitely at the present 
time, but the past existence of large desert tracts in the north 
of this country is quite a feasible suggestion, and the geological 
evidence, as it stands at present, is, perhaps, rather in favour of 
it than otherwise. 

