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Proceedings of the Royal Society 
it can scarcely be allowed that the same influence is exerted, or can 
possibly be exerted, in tropical lands. No man was less in danger 
of taking a provincial view of nature than Mr Darwin, and in 
discussing the earth-worm he has certainly collected evidence from 
different parts of the globe. He refers, although sparingly, and 
with less than his usual wealth of authorities, to worms being found 
in Iceland, in Madagascar, in the United States, Brazil, New South 
Wales, India, and Ceylon. But his facts, with regard especially 
to the influence on the large scale of the worm in warm countries, 
are few or wholly wanting. Africa, for instance, the most tropical 
country in the world, is not referred to at all ; and where the 
activities of worms in the tropics are described, the force of the 
fact is modified by the statement that these are only exerted during 
the limited number of weeks of the rainy season. 
The fact is, for the greater portion of the year in the tropics the 
worm cannot operate at all. The soil, baked into a brick by the 
burning sun, absolutely refuses a passage to this soft and delicate 
animal. During the brief period of the rainy season worms un- 
doubtedly carry on their function in some of the moister tropical 
districts ; and in the sub-tropical regions of South America and 
India worms, small and large, appear with the rains in endless 
numbers. But, on the whole, the tropics proper seem to be poorly 
supplied with worms. In Central Africa, though I looked for them 
often, I never saw a single worm. Even when the rainy season set 
in, the closest search failed to reveal any trace either of them or of 
their casts. Nevertheless, so wide is the distribution of this animal, 
that in the moister regions even of the equatorial belt one should 
certainly expect to find it. But the general fact remains. Whether 
we consider the comparative poorness of their development, or the 
limited period during which they can operate, the sustained per- 
formance of the agricultural function by worms, over large areas in 
tropical countries, is impossible. 
Now, as this agricultural function can never be dispensed with, it 
is more than probable that nature will have there commissioned 
some other animal to undertake the task. And the animal we are 
in search of, and which I venture to think equal to all the neces- 
sities of the case, is the termite, or white ant. This animal, the 
popular name of which is misleading, seeing that it belongs to the 
