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about the grass on some boggy land on which two men had just
trampled while setting a trap； and this occurred in a part of
Ireland where there were no moles。 I have been assured by a
Volunteer that he has often seen many large earth…worms crawling
quickly about the grass； a few minutes after his company had fired
a volley with blank cartridges。 The Peewit （Tringa vanellus；
Linn。） seems to know instinctively that worms will emerge if the
ground is made to tremble； for Bishop Stanley states （as I hear
from Mr。 Moorhouse） that a young peewit kept in confinement used to
stand on one leg and beat the turf with the other leg until the
worms crawled out of their burrows； when they were instantly
devoured。 Nevertheless； worms do not invariably leave their
burrows when the ground is made to tremble； as I know by having
beaten it with a spade； but perhaps it was beaten too violently。
The whole body of a worm is sensitive to contact。 A slight puff of
air from the mouth causes an instant retreat。 The glass plates
placed over the pots did not fit closely； and blowing through the
very narrow chinks thus left； often sufficed to cause a rapid
retreat。 They sometimes perceived the eddies in the air caused by
quickly removing the glass plates。 When a worm first comes out of
its burrow； it generally moves the much extended anterior extremity
of its body from side to side in all directions； apparently as an
organ of touch； and there is some reason to believe； as we shall
see in the next chapter； that they are thus enabled to gain a
general notion of the form of an object。 Of all their senses that
of touch； including in this term the perception of a vibration；
seems much the most highly developed。
In worms the sense of smell apparently is confined to the
perception of certain odours； and is feeble。 They were quite
indifferent to my breath； as long as I breathed on them very
gently。 This was tried； because it appeared possible that they
might thus be warned of the approach of an enemy。 They exhibited
the same indifference to my breath whilst I chewed some tobacco；
and while a pellet of cotton…wool with a few drops of millefleurs
perfume or of acetic acid was kept in my mouth。 Pellets of cotton…
wool soaked in tobacco juice； in millefleurs perfume； and in
paraffin； were held with pincers and were waved about within two or
three inches of several worms； but they took no notice。 On one or
two occasions； however； when acetic acid had been placed on the
pellets； the worms appeared a little uneasy； and this was probably
due to the irritation of their skins。 The perception of such
unnatural odours would be of no service to worms； and as such timid
creatures would almost certainly exhibit some signs of any new
impression； we may conclude that they did not perceive these
odours。
The result was different when cabbage…leaves and pieces of onion
were employed； both of which are devoured with much relish by
worms。 Small square pieces of fresh and half…decayed cabbage…
leaves and of onion bulbs were on nine occasions buried in my pots；
beneath about 0。25 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 given together； the latter were always； and manifestly
preferred。 Leaves of the cabbage； lime…tree； Ampelopsis； parsnip
（Pastinaca）； and celery （Apium） were likewise given together； and
those of the celery were first eaten。 But when leaves of cabbage；
turnip； beet； celery； wild cherry and carrots were given together；
the two latter kinds； especially those of the carrot； were
preferred to all the others； including those of celery。 It was
also manifest after many trials that wild cherry leaves were
greatly preferred to those of the lime…tree and hazel （Corylus）。
According to Mr。 Bridgman the half…decayed leaves of Phlox verna
are particularly liked by worms。 ｛16｝
Pieces of the leaves of cabbage； turnip； horse…radish and onion
were left on the pots during 22 days； and were all attacked and had
to be renewed； but during the whole of this time leaves of an
Artemisia and of the culinary sage； thyme and mint； mingled with
the above leaves； were quite neglected excepting those of the mint；
which were occasionally and very slightly nibbled。 These latter
four kinds of leaves do not differ in texture in a manner which
could make them disagreeable to worms； they all have a strong
taste； but so have the four first mentioned kinds of leaves； and
the wide difference in the result must be attributed to a
preference by the worm