THE OREGON SUNDAY JOURNAL, PORTLAND, : SUNDAY .. HORNING, T.TAVv 12, 1907
x . ' r . ' 'I.I , . . i , " , . ,
.!;V - .,: ' Av N i
1 ' . .
! i
r
1 dy &aby0oo3 ' ,
JO PLANTS see,
y feel, hear, tat tet
: smellf Inallseri.
tmsness, do fbeyf ' ;
Tost A question
aside with disdain if you.
ft7 leading botanical
. authorities of the United
States, chiefs of botanical
departments in great instu :
tutions of learning, have
concluded that the subject
' b tvell worth devotinr aU I --J
- . - o -
tention to. In Baltimore,
'Chicago Philadelphia, Los,
Angeles, simultaneously ,
experiments are b ein g
made by men who promise
most interesting results '
" :. from this study v C ; ;
And they have already -learned
some, startling
- things. .V: -: v r
. , 0 course,' they 'don't '
attempt ", to prove that '
plants have eyes, ears, nos
trils, palates, fingers, : but
they do say that they ex
hibit characteristics corre
spending to the five human ;
: senses. iyi-VfV'-;
A Baltimore authority
balks at one sensehear- 1
if g but 4 Philadelphia , " ,
botanist, Professor John Muirhead Mac
farland, D. Sc., declares that ecen this may
; granted, since a revolver shot in a green
house will cause a collapse of all the sensi
tive plants. At least, they respond to sound
waves,
'A number of plants, it Is found, are
equipped with elongated hairs, or else spots,
which catch the , lights about as does the
human eye. Certain plants turn up their;
leaves to gather in the life-giving rays of ;
the sun; others travel: to' seek food and
light; still others find their way through air
to a stick upon which to twine. .
Hop : and . sweet potato vines go
through rotary motions; controlled by the ,
movements of the ; earth ; and sun J The
Venus Hs-trat catches insects whose flavor
it UkesM Hence "lasteMi Similarly, a root
will pna m way to a favorite material tn
the soil-will smell it cutj so to speak. - .
Even such emotions as joy and sadness
are, so some investigators say experienced
by plants; they are thankful for moisture
M me air; tney jteep every mm.
'Pi.:-' ;
'v'..";:.fc. .
0:- .yay '
1 :a
i;v ,Nv ' " ' -
1-
V
?'
A
12, plaoU do Dot, tt to bellersd, contain th
pbaomena correa ponding to mmm.m Jean,
to soma plants tha facultlaa ara mora pro
nounced than In other, and o ' tber ara
Sroupad under thrbead of 'aenalUTa' plants. .' ' v
Soma of thera bare ben found In the tropics, oth
' an in rarlous portions of America, and not a few of
them . soma of tha most important. ln.Xac6-r among
common American domestlo plants: for lnstanoa, the ,
bop. . ' ; - ' , - " '
Students ta botany at tha University of Pennejrl
" vanla have lately been maklns- soma Interesting- experl-
wants to determine Just to what extent the bop and
sweet potato vines ara endowed with motion re
sembling the animal kind.
There is aothinr strange about any plant morlng
, with the wind or In the natural prooess of growth,
but these motions ara not of that eort..
Tha and of a vine usually hangs free, its leaves r
- lnlllnr mj-tttiillw In tha air. Tet every one of them.
unleM its , course be impeded by soma object;, will
every day make a complete revolution, ;. or witiv
describe an are of half a circle,-then slowly go back -to
its starting point. ' -
, litis, it is believed, IS no accident, but is the direct
effect of the sun's influence opposed to the' diurnal
motion of the earth, with,, perhaps, something of tha
earth's gravity mixed in. 4
Botanists do not say that it is dons consciously,,;
thiv hM At iWint.nil thu tha mntlnn rt thk vln la thk
rusult of centuries, aeons, of constant attempt to ad- .
just itself to the mighty forces operating upon It
As an illustration. of bow the sense of touch is do 1
veloped in plant life, a botanist the other day gave
a demonstration With a plant of tha mimosa pudica
' speclns. - This is a plant which grows (in pots) to the .
' sterna, each stem containing four leaves. - The leaC -.
is couipoaed of many little segments, sticking out from
. the vein. '- a:,, 'L- -
The segments In the plant exhibited were beautl-
fully - unrolled; tha stems stood out from , the stalk. . :
wask passed on, " by soma mysterious agency within
the Vein, to tha next leaf: . the stimulation passed
through the Joint at tba tarmlnus of the loaf and
went on to the end. '
Next cams tha third leaf, then the fourth, the mo-
"7tlon becoming mora rapid as it progressed. And when
' - tha four leaves were down, suddenly, as if chopped by
an axe, the entire stem collapsed and bung apparent
Jy lifeless against the stalk. 'i':' 1 , '
' Again, the botanist gave a slight stroke to tha
stalk below tha stems, and every stem, every leaf,
vary; segment, collapsed. tK'V-! .' '
Ton might have thought from the appearance that
alLuer horlxontallv op at an unward ancla.
Carefully seizing two segments at the very end
ef a leaf tha professor said: "Now watch." He
pinched tha green matter slightly cot enough to
bruis it
Immediately the next pnlr of segments on either
stfle of the vein fell down tiat. utterly collapsed. An
Umlaut later the next pair dropjwd. . .
i rora that on It was Jiit like clockwork: pair
after pair u la rapid suoceaslon until the last pair
reached. : s
Just a moment's pause, and then tha same aotloa
the plant was dead, but in tan minutes It bad gradu
ally regained its normal shape. '
Just why the "plant exhibits such characterlsUos
. Is not known. Even those who say that plants have
no sense of touch are unable to oiler any explana
tion more plausible. ' ', . , ' i ' 1 - V
But one very Important experiment has shown,
or tended to show, that tha phenomena are actually
controlled or to be accounted for, by a sense.
" A"'mlmosa plant was etherized the - anaestbetto '
was applied to it in much the same manner-as it
would have bean given to a human bflng in a den
tist's chair, or on an operating table. - -
Mnch a person who is under ether, and there is
no response; he doesn't feel it
Now, thought the. botanists, if the mimosa be not
affected by eiher, it will show that it has no sense,
but merely mechanical action; if it be affected by the
drug, tha leaves wwnot couapse wnen you pincn .
, tbego they pinched and pinched, and hot a bit did'
. the plant mind it. There was no fallhig of segroenu .
or leaves. And after awhile, when the plant "came
out of ether," It acted Just as before, that is, as
sumed Us normal ''senses." ' '
To compare still further, plants of the mimosa
' pudica order have been experimented with under the
' same conditions as a human muscle., , -
Strike or pinch a muscle repeatedly, and it re
sponds to each stimulus, remaining contracted in a -condition
Of tetsnus. ; . ;j
This is true of the oxalls plant, but not of the
mimosa pudica, so that the conclusion to be drawn
Is somewhat In shadow. - ;
, But one strong deduction Is -that, since plants of
ptently similar type possess different forms of ao- .
tlou under the same circumstance, they must be pos
sessed of something mors than phenomena. What,'
v. then senses? ;- -.- ,""f-v''
Tha oxaUs plant, while apparently of the same
species, differs in some important respects from the:
mimosa. It is ' of the trefoil kind three leaves ex-
tending from a Stem. Upon being shaken, these leaves
i collapse about the stem, but upon a second shaking
' they will fly to their natural position and CJhape. '
- Indeed, the conclusion has been f oread upon soma
' of the f reatest botanists that the sensation of con- -tact
is produced in plants and animals under tha
same or similar conditions.
.... I I v
i ft"
1 M
' .',
mm.
. ' . .,. . ' .' : t .'!
lw.l . J:
sff i SSy : v:l??f II
V ,
Nature has fitted these plants with a sense of
touch, or feeling, she surely must hava had s pur-
posa, ' . ' . , l
In the oasa of ths mimosa this reason la bs ,
Ueved to bo that. ths collapse at ft slight touch aid ;
in keeping off large browsing; animals, also attacks
of injurious Insects.-
goat, seeing his prospective meal dwindle, , -leaves
It for mors favorable past? rage ft fly IS ;
scared away, by ths coUspss of leaves. Ths oloslnf
lsavss Is also protection ag-ainst rata or hall. '
In ens class of plants the Utility evldenUy list
ln'lnsuring ths transfersncs or reception of poUenx '
In ' another, ths ' capture and digestion of insects, ,
Why ths oxalls leaves collapse whea touched Is nst
A visitor who called at an experiment green-
was ,
Tinior wno cauea at an experiment i
house at twilight to see ths sensitive Plants
surprised to be told by the attendant: "I fear J
will see very little of them, for they're all asleep."
They go to sleep when ths su
their leaves alter me same
For example, apply a slight electric shock to a man. and ths epidermis is tickiea:
do the same to a tendril plant, and it undergoes gyrations which botanists say are
nothing less than indications of being tickled.
And if one were to admit a solar plexus, one must perforce admit some of the
senses. -j :.. v.is-;,-' 5-.;--..
That certain highly sensitive plants respond to sudden variations In the atmos
pherlo pressure has Ions been known.
He meant it
goes down, closinsr ud
fashion as when stimulated.
It was suggested that, perhaps,1 this was
purely mec&anical act, and night not mean that th
Plants were aaulDDed with - fu. uliles norrasDondlni
: to the human senses, which needed rest.
. "8tlU." responded the ooUnist ,fyou will admit
It strange that no amount of artificial light or alee
trioal current or other treatment can arouse then
; from sleep." It was, indeed, an odd observation.
- In that greenhouse there was a sort of divine
, calm which seised hold uoon the visitor. One felt
that the plants were really asleep, not simply close j
, up mechanically, and that they breathed forth some
of their peace. -
. And speaking of breathing, it Is weU established
' that plants inhale and exhale atmosphere Just as
animals do, with some slight variation, for, where
-as the- animal- inhales-cren and exhales carbon
dloxld, : the plant-thrives on carbon dioxid and give
out oxygenv A sort of peetlo reciprocity. . . .
Do plants really see? . -
' Of course, to speak of a plant seeing, ons mast
presume - eyes. , No one has been bold enough td
say that plants have eyes in tha same sense as ani
mals, but, say the botanists, there at, several kinds
of organisms that servs the same purpose.
In at least two Instances in the oases of the
pertalonia and begonia there stick up from the
surface of the leaves innumerable little elongated
hairs with slight swelling on ths snds.
. . These hairs, say the botanists.- correspond te
the retlna of the eye: they collect ' stray rays of
light and pass them downward as light rays are
carried by the optio nerve for tha human eye into
the leaf where they mean nourishment, 11e.
5 -In another case tha Bf tonia plant muollaginous -spots
all over the surface of the leaf are somewhat
poetically held to servo the purpose of eyes, .'-
iuru a. .ayout,, ueu.il vina upsian aown piaclnok,
woven wire over the mouth of the pot so ths dirt
will not spill out-and watch it, ,
The leaves which , at first hang downward so
'evenly will soon curl upward first ths leaves, then
iu uu uuu Muujt lueir nnai posi '
.tion. T (;..,.'-.'. i,.- .-.- . -r ...
This means sight1 The' leaves are looking for
the light the sun and .when they find it, stop and'
look serenely at it v
"Have you done anything to prove that plants'
possess the sense of smell r one of ths lnvesflgators
was asked. . " . ",;
"les," he replied. .If you place dirt In a bo
' with glass sides and plant s seed so you can watch
its growth through ths glass, you may note a curi
ous thing. ,u-w,y ; . ..''......-.,',';i 7.
"Suppose there are In that dirt out of line with
the vertical direction at first taken by the seed root
, certain substances, such as arsenic and starch!
u. Yott will see. every time, the root turn lu course
. toward the substance it likes in this instance, the
: starch. If-that isn't smell what Is itf. O
That plants grow from protoplasm,' as animals
do, is generally accept el. That they ara but a
- lower form of animal life is a natural conclusion.
. That they contain in essence those characteristics
which, in a more highly developed life, become
known as senses who cut prove that this Is not
the next logical step T ..."
ft;-
, .-'.r. 7 ; :' i ,7 r , :: r 'i