FUNGI. 331 
tropical forests, where the exuberance of the vege- 
tation excludes the rays of the sun, and creates the 
dim light and the still, moist air which they love, 
and where there is always an immense quantity 
of decaying organic matter, we might expect to 
find them in the greatest quantity and luxuriance. 
But, strange to say, fungi.as a class are compara- 
tively rare in tropical woods. While every tree 
has its creeper, and almost every flower its para- 
site, the plants which, above all others, are most 
parasitical have relatively few representatives 
there ; and dead trunks and prostrate boughs and 
decaying herbage rot and crumble away un- 
touched by the ravages of mushroom or mould. 
Insects in these countries perform the office of 
fungi in hastening the decomposition of dead 
matter, and incorporating and deodorizing the de- 
caying particles ; and it must be confessed that 
they perform this duty more speedily and effectu- 
ally ; while, unlike the fungi, they leave no un- 
pleasant traces, no putrifying masses behind when 
their work is accomplished, and their own turn 
comes to die. Like some of the epidemic diseases, 
as, for instance, typhus, with which they are said 
to be connected, the too high temperature of the 
tropics seems to offer an effectual barrier to 
their general distribution in those countries, 
Their head-quarters seem to be in northern lati- 
