In the year 1869, Mr. Fish {5} rejected my conclusions with respect
to the part which worms have played in the formation of vegetable
mould, merely on account of their assumed incapacity to do so much
work. He remarks that "considering their weakness and their size,
the work they are represented to have accomplished is stupendous."
Here we have an instance of that inability to sum up the effects of
a continually recurrent cause, which has often retarded the
progress of science, as formerly in the case of geology, and more
recently in that of the principle of evolution.

Although these several objections seemed to me to have no weight,
yet I resolved to make more observations of the same kind as those
published, and to attack the problem on another side; namely, to
weigh all the castings thrown up within a given time in a measured
space, instead of ascertaining the rate at which objects left on
the surface were buried by worms. But some of my observations have
been rendered almost superfluous by an admirable paper by Hensen,
already alluded to, which appeared in 1877. {6} Before entering on
details with respect to the castings, it will be advisable to give
some account of the habits of worms from my own observations and
from those of other naturalists.

[FIRST EDITION, October 10th, 1881.]



CHAPTER I--HABITS OF WORMS.