IN THE SWAMP. 219 



glow at night. It is this also that tinges all the 

 water of the creeks, making them of the well- 

 known coffee colour which has given rise to the 

 name of Rio Negro, so often applied to South 

 American rivers. Unlike peat it is not fibrous, 

 but apparently made up of layers, which in dry 

 seasons can be separated one from another, and 

 proved to consist of thin strata of leaves. It is 

 somewhat elastic under foot when dry, but sinks 

 at every step with a crunching noise on account 

 of its brittleness. When drained and put under 

 cultivation, pegass lands gradually sink until their 

 level is lowered about two feet, as the vegetable 

 matter being exposed undergoes thorough de- 

 composition in the full sunlight. Like the reduc- 

 tion of fallen trees in the forest to a rich humus, 

 the breaking down of the cast-off leaves in the 

 swamp is an entirely different operation to that 

 which goes on under other conditions, and is well 

 worth studying. The main factors concerned are 

 moisture and the absence of direct sunlight, 

 perhaps combined with the antiseptic properties 

 of tannin which is found more or less in the bark 

 and roots of all the trees and plants. However, 

 we must return to the great razor grass, which 

 might now be thought gone past recovery. 

 Nothing remains but its blackened tufts and you 



