274 
BLUEFIELDS. 
never wanting, and slender flexible Lianes of great 
length dangle in the air from the lofty branches. 
In general a tropical forest knows no such phe- 
nomenon as the fall of the leaf ; that is, the decay of 
some and the unfolding of other leaves proceed simul- 
taneously and constantly, so that the foliage is ever 
full, and ever verdant. There are however a few ex- 
ceptions of trees, which are periodically denuded, and 
stretch out their naked arms, as if they had ex- 
perienced the chill blasts of a northern November. 
The Tropic Birch {Bursera) is one of these, and the 
Cotton- tree is another. The latter I have seen almost 
wholly stripped of its full foliage in the course of an 
hour, during a tempestuous gust of wind in July. It 
remains bare for several months, the young leaves 
appearing about the end of May. The green pods 
in the meantime have formed, ripened, and burst, 
liberating a quantity of flne silky fllamentous down 
of a pale brown colour. At first sight one is ready to 
say. What a pity that a material so cotton-like and so 
abundant should be suffered to fly about upon the 
breeze, instead of being collected for manufacturing 
purposes ! But in reality it is incapable of being so 
used, the fibres being found to possess no power of 
mutual cohesion. Under the microscope they are 
seen to be simple cylindrical transparent tubes, some- 
times flattened, but having neither the twisted form 
of true cotton, nor the jointed appearance of linen, 
nor the imbricated surface of wool. They are some- 
times used to stuff pillows and mattrasses ; and the 
Palm Swift and the different species of Humming- 
birds And in them a material sufficiently soft and 
warm for the reception of their tender young. The 
