of Edinburgh, Session 1884-85. 
137 
3. On the Termite as the Tropical Analogue of the 
Earth-Worm. By Professor Henry Drummond. 
My object in this paper is to call attention to a few observations 
which occurred to me during a recent scientific survey of part of 
Central Africa, regarding the larger economy of tropical nature. 
And I wish especially, and with much deference, to attempt to 
supplement a well-known theory of Mr Darwin’s, by bringing 
forward another claimant to the honour of being, along with the 
earth-worm, the leading organic agricultural and geological agent in 
nature. 
By means of inorganic agencies — the air, the frost, and the rain — 
nature has no difficulty in any part of the world in preparing 
surface films of disintegrated soil for the growth of vegetable life. 
But though the elaboration of a surface film by these agencies 
would produce crops for a few years, a much more radical system 
of agriculture must be in operation before a prolonged succession of 
crops can be kept up from year to year, and from century to 
century. The lower layers of soil, exhausted with bringing forth, 
must be constantly transferred to the top ; while the upper layers, 
restored, disintegrated, and saturated with the fertilising products 
of organic decomposition, must be lowered down to where the 
rootlets spread themselves in the under soil. The patient series of 
observations by which Mr Darwin established the conclusion that 
this function was discharged by the earth-worm are too well-known 
for repetition. On every acre of land in England, Mr Darwin 
calculates that more than 10 tons of dry earth, are passed through 
the bodies of worms, and brought to the surface every year; and he 
assures us that the whole soil of the county must pass and repass 
through their bodies every few years. “ The plough,” he says, “is 
one of the most ancient and most valuable of man’s inventions ; 
but long before he existed the land was, in fact, regularly ploughed 
by earth-worms. It may be doubted whether there are many other 
animals which have played as important a part in the history of the 
world as have these lowly organised creatures.”* 
How, while admitting to the fullest extent the influence of 
worms in countries which enjoy a temperate and humid climate, 
* Vegetable Mould and Earth- Worms, p. 313. 
