SELBORNE, _May_ 20_th_, 1777.
Dear Sir,--Lands that are subject to frequent inundations are always
poor; and probably the reason may be because the worms are drowned. The
most insignificant insects and reptiles are of much more consequence, and
have much more influence in the economy of Nature than the incurious are
aware of, and are mighty in their effect, from their minuteness, which
renders them less an object of attention, and from their numbers and
fecundity. Earth-worms, though in appearance a small and despicable link
in the chain of Nature, yet, if lost, would make a lamentable chasm. For,
to say nothing of half the birds, and some quadrupeds, which are almost
entirely supported by them, worms seem to be the great promoters of
vegetation, which would proceed but lamely without them, by boring,
perforating, and loosening the soil, and rendering it pervious to rains
and the fibres of plants, by drawing straws and stalks of leaves and
twigs into it, and, most of all, by throwing up such infinite numbers of
lumps of earth called worm-casts, which, being their excrement, is a fine
manure for grain and grass. Worms probably provide new soil for hills
and slopes where the rain washes the earth away; and they affect slopes,
probably to avoid being flooded. Gardeners and farmers express their
detestation of worms; the former because they render their walks
unsightly, and make them much work; and the latter because, as they
think, worms eat their green corn. But these men would find that the
earth without worms would soon become cold, hard-bound, and void of
fermentation, and consequently sterile; and besides, in favour of worms,
it should be hinted that green corn, plants, and flowers, are not so much
injured by them as by many species of _coleoptera_ (scarabs), and
_tipuloe_ (long-legs) in their larva, or grub-state, and by unnoticed
myriads of small shell-less snails, called slugs, which silently and
imperceptibly make amazing havoc in the field and garden. {86}
These hints we think proper to throw out in order to set the inquisitive
and discerning to work.
A good monography of worms would afford much entertainment and
information at the same time, and would open a large and new field in
natural history. Worms work most in the spring, but by no means lie
torpid in the dead months: are out every mild night in the winter, as any
person may be convinced that will take the pains to examine his grass-
plots with a candle; are hermaphrodites, and very prolific.