the formation of vegetable mould-第4节

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and　the　other　worm　when　C　in　the　treble　clef　was　struck。　　On　these　
occasions　the　worms　were　not　touching　the　sides　of　the　pots；　which　
stood　in　saucers；　so　that　the　vibrations；　before　reaching　their　
bodies；　had　to　pass　from　the　sounding　board　of　the　piano；　through　
the　saucer；　the　bottom　of　the　pot　and　the　damp；　not　very　compact　
earth　on　which　they　lay　with　their　tails　in　their　burrows。　　They　
often　showed　their　sensitiveness　when　the　pot　in　which　they　lived；　
or　the　table　on　which　the　pot　stood；　was　accidentally　and　lightly　
struck；　but　they　appeared　less　sensitive　to　such　jars　than　to　the　
vibrations　of　the　piano；　and　their　sensitiveness　to　jars　varied　
much　at　different　times。

It　has　often　been　said　that　if　the　ground　is　beaten　or　otherwise　
made　to　tremble；　worms　believe　that　they　are　pursued　by　a　mole　and　
leave　their　burrows。　　From　one　account　that　I　have　received；　I　have　
no　doubt　that　this　is　often　the　case；　but　a　gentleman　informs　me　
that　he　lately　saw　eight　or　ten　worms　leave　their　burrows　and　crawl　
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　worms　for　one　taste　over　another。

Mental　Qualities。There　is　little　to　be　said　on　this　head。　　We　
have　seen　that　worms　are　timid。　　It　may　be　doubted　whether　they　
suffer　as　much　pain　when　injured；　as　they　seem　to　express　by　their　
contortions。　　Judging　by　their　eagerness　for　certain　kinds　of　food；　
they　must　enjoy　the　pleasure　of　eating。　　Their　sexual　passion　is　
strong　enough　to　overcome　for　a　time　their　dread　of　light。　　They　
perhaps　have　a　trace　of　social　feeling；　for　they　are　not　disturbed　
by　crawling　over　each　other's　bodies；　and　they　sometimes　lie　in　
contact。　　According　to　Hoffmeister　they　pass　the　winter　either　
singly　or　rolled　up　with　others　into　a　ball　at　the　bottom　of　their　
burrows。　｛17｝　　Although　worms　are　so　remarkably　deficient　in　the　
several　sense…organs；　this　does　not　necessarily　preclude　
intelligence；　as　we　know　from　such　cases　as　those　of　Laura　
Bridgman；　and　we　have　seen　that　when　their　attention　is　engaged；　
they　neglect　impressions　to　which　they　wo