square pieces of fresh and half-decayed cabbage-leaves and of onion bulbs
were on nine occasions buried in my pots, beneath about 1 4 of an inch of
common garden soil; and they were always discovered by the worms. One
bit of cabbage was discovered and removed in the course of two hours;
three were removed by the next morning, that is, after a single night;
two others after two nights; and the seventh bit after three nights. Two
pieces of onion were discovered and removed after three nights. Bits of
fresh raw meat, of which worms are very fond, were buried, and were not
discovered within forty-eight hours, during which time they had not
become putrid. The earth above the various buried objects was generally
pressed down only slightly, so as not to prevent the emission of any
odour. On two occasions, however, the surface was well watered, and was
thus rendered somewhat compact. After the bits of cabbage and onion had
been removed, I looked beneath them to see whether the worms had
accidentally come up from below, but there was no sign of a burrow; and
twice the buried objects were laid on pieces of tin-foil which were not
in the least displaced. It is of course possible that the worms whilst
moving about on the surface of the ground, with their tails affixed
within their burrows, may have poked their heads into the places where
the above objects were buried; but I have never seen worms acting in this
manner. Some pieces of cabbage-leaf and of onion were twice buried
beneath very fine ferruginous sand, which was slightly pressed down and
well watered, so as to be rendered very compact, and these pieces were
never discovered. On a third occasion the same kind of sand was neither
pressed down nor watered, and the pieces of cabbage were discovered and
removed after the second night. These several facts indicate that worms
possess some power of smell; and that they discover by this means
odoriferous and much-coveted kinds of food.
It may be presumed that all animals which feed on various substances
possess the sense of taste, and this is certainly the case with worms.
Cabbage-leaves are much liked by worms; and it appears that they can
distinguish between different varieties; but this may perhaps be owing to
differences in their texture. On eleven occasions pieces of the fresh
leaves of a common green variety and of the red variety used for pickling
were given them, and they preferred the green, the red being either
wholly neglected or much less gnawed. On two other occasions, however,
they seemed to prefer the red. Half-decayed leaves of the red variety
and fresh leaves of the green were attacked about equally. When leaves
of the cabbage, horse-radish (a favourite food) and of the onion were
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