2a6 IN THE GUIANA FOREST. 



paratively few and far between, so that they 

 hardly overshadow the undergrowth of sedges, 

 only preventing it from becoming so dense as in 

 the open savannah. Instead of these characters 

 being signs of degradation however, close obser- 

 vation appears to indicate that, like every other 

 living thing in their neighbourhood, they have 

 been developed to suit special conditions and 

 circumstances. It is obvious that a large and 

 heavy crown would tend to bring down the tree 

 with its weight when loosened by the flood. 

 Therefore, like most of the shrubs under the same 

 circumstances they spread their roots over the 

 pegass and take care not to provide a mass of 

 foliage which would obstruct the flow of the water 

 when it is high, or tend to overthrow them by 

 becoming top-heavy. The effect of all this is 

 beautifully illustrated in the Cabomba ; as long as 

 it grows under water, only feathery leaves are 

 produced, but when it reaches the surface it covers 

 the water with its pretty shields. Something 

 similar takes place with the tree ; in the swamp 

 its branches are numerous and open, while in the 

 forest it produces a thick canopy of foliage at the 

 top of a naked trunk. 



That the struggle for life in the swamp is more 

 intense than that in the forest can easily be under- 



