oosening and pulverizing
of the packed earth; the mixing of dead leaves and other vegetation on
and near the surface with the more solid earth farther down; the letting
in of water and air; and the checking of loss of water through cracks
the sun forms by baking the soil dry.
The earthworm is a creature of the dark. It cannot see, but it is
sufficiently sensitive to light to avoid the sun, the rays of which
would shrivel up its moist skin. Having no lungs or gills, the worm uses
the skin as the breathing organ; and it must be kept moist in order to
serve its important use. This is why earthworms are never seen above
ground except on rainy days, and never in the top soil if it has become
dry. In seasons of little rain, they go down where the earth is moist,
and venture to the surface only at night, when dew makes their coming up
possible.
Earthworms have no teeth, but they have a long snout that protrudes
beyond the mouth. Their food is found on and in the surface soil. They
will eat scraps of meat by sucking the juices, and scrape off the pulp
of leaves and root vegetables in much the same way. Much of their
subsistence is upon organic matter that can be extracted from the soil.
Quantities of earth are swallowed. It is rare that an earthworm is dug
up that does not show earth pellets somewhere on their way through the
long digestive canal. The rich juices of plant substance are absorbed
from these pellets as they pass through the body.
Earthworms explore the surface of the soil by night, and pick up what
they can find of fresh food. Nowhere have I heard of them as a nuisance
in gardens, but they eagerly feed on bits of meat, especially fat, and
on fresh leaves. They drag all such victuals into their burrows, and
begin the digestion of the food by pouring on it from their mouths a
secretion somewhat like pancreatic juice.
The worms honeycomb the earth with their burrows, which are long,
winding tubes. In dry or cold weather these burrows may reach eight feet
under ground. They run obliquely, as a rule, from the surface, and are
lined with a layer of the smooth soil, like soft paste, cast from the
body. The lining being spread, the burrow fits the worm's body closely.
This enables it to pass quickly from one end to the other, though it
must wriggle backward or forward without turning around.
At the lower end of the burrow, an enlarged chamber is found, where
hibernating worms coil and sleep together in winter. A
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