The sun. [volume] (New York [N.Y.]) 1833-1916, 1894-08-26

fully peruscd, but perhaps the most widespread
interest Is likely 10 attach IN those treating OF
the border territory between the animal and tho
vegetable kingdom. Of the relation Of paleontol-
ogy to the doctrine OF evolution, and of the for
nation OF coal.
-Four distinctions were drawn by Cuvier In
1928 between animals and vegetables. The for
mer, hn said. were mobile, the latter not. and
from the mobility of animals he deduccd, by
archaeological reasons. the necessity Of the ex-
istencc In them OF an alimentary cavity or reser-
voir ot food. The second great distinctive
character of animals he found in the circulatory
system, which. however. he recognized rs less
important than the digestive. since he knew "
TO be absent In the NOR , simple animals. In the
CONSUMPTION Of nitrogen 10y animals he placed
the third distinction between them Gnd the
nlants. In his belief, also, respiration, that Is.
the absorption Of oxygen and tho cShalation Of
carbonic acid, was n special fuhctlon Of
animals. and constituted their fourth dis
tinctive character. What has become Of these
distinctions in tho light of the science OF our
day. At the present time innumerable plants
and free plant cells are known TO pass the whole
or part OF their lives in an actively locomotive
condition In no wise distingulshablc from that Of
one OF the simpler animals. and while in this
condition their movements are, To all appear
nnce. as SDDntnne DuS as mCCn inc product OI
volition--as those of such animals. Hence the
Theological argument for Cuvler's first disgnos-
tic charaotcr-the presence in animals OF an ali
mentary cavity or internal pocket in which they
can carry about their nutrlmcnt-- has broken
down. at least so far as his mode Of stat
ing 1t goes. With tho advance. moreover. of
microscopic anatomy. the universality of the
fact itself among animals has ceased TO be pred
icable. Many animals of even complex struc-
49, -. H. tai H. Ia 4 - -
wholly devoid Of an alimentaTy cavity. Their
food Is provided for them not only ready cooked,
but ready dig, stcd, and the aliinentary canal,
having become supcrfuous. has disappeared.
Again. the males Of most Rotifcrs have no di-
gestive apparatus: "a a German naturalist has
remarked. they devote themselves entirely 10
the MlnnedieEs3 or sexual act. and are to be
reckoncd among the few reallzations of tho
Byronic id,a o. n lover. Finally. amid
the lowest 20 ms of animal life the speck OF
gelatlnois protoplasm which constitutes the
whole body has no permanent digestive cavity
or mouth, but takes in its food anywhere. and
digests, 30 To speak, all over its body. Never
thelcss, although Cuvi,r's leading diagnosis of
the animal fro the plant will rot bear n strict
test. 1t remains one OF tho most constant of the
distinctive characters of animals. IL we substi-
tute for the DOS session OF an alimentary cavity
the power of taking solid nutriment into the
.'sys AHh ''hNhN 80 ~ go AAsshhh' W
changed will cover all animals, except certain
parasites and tho few and exceptional cases Of
non-parasitlc animals which do not feed.
On the other hand. the definition thus amended
will exclude all ordinary vegetable organisms.
AS to the second distinctive mark. r clrcula-
tory system, Crvior himself practically gives ID
up when he nd mits that II Is wanting In the sim
pier animals. The third distinction-tha the con-
sumption OF nitrogen il peculiar to animals-is
based on n complies y erroneous conception OF
the chemical Differences and resemblances be-
tween the constituents OF animal and vegetable
organisms. for which Cuvler is not responsible,
as IL was current among contemporary chem
lists. IL Is now established that nitrogen Is as
essential a con sti;uent of vegetable rs OF animal
living matter. and that the latter IL. chemically
speaking, just rs complicated as the former.
Starchy substances. celluloss and sugar. once
supposed to be exclusively conined.to plants, are
now known to lbs regular and normal products
OF animals. Amyiaceous and saccharino sub
stances are largely manufactured, even by the
highest animals; ccllulOse IL widespread as a
constituent of the skeletons OF tho lower ami
mails. and ID Is probable that smyloid substances
are universally present in the animal organ
tsms. though not In the precise form OF starch.
We come lastly to respiration, and we lind
that. although IL remains true that there Is an
inverse relation between the green plants In sun
shine and the animals, In 30 far as that, under
the circumstances, the green plant ~decomposes
carbonlc acid and exhales oxygen, while the
animal abs0rbs oxygen and exhales carbonic
acid, yet the exact researches OF modern chem
icnl Investigators of the physiological pro-
cesses OF plants have clearly demonstrated the
faliacy of attempting 90 draw any distinction
between animals and vegetables on this
ground. In fact, the difference vanishes
with the sunshine. even in the case
OF the green plants, which. In the dark. absorb
oxygen and give out carbonic acid, like any
animal. On the other hand, those plants. such
as the fungi. which cont ain no chlorophyll and
arc not green. are always, whether In tho dark
or In the sunshine. 50 far as respiration is con-
oerned, In the exact position OF animals. They
absorb oxygen and give out carbonic acid.
There Is. IN truth, every reason to believe that
all living plants, like living animals, always
respire In sunshine or in the dark, and, In
respiring, absorb oxygen and give OF carbonic
acid: but that, in green plants exposed TO day
light or IN the electric light, the quantity OF
oxygen evolved in consequence OF the decom-
position of carbOnic acid by a special apparatus
which green plants possess exceeds that alb
sorbed in the concurrent respiratory process.
Thus, by the progress of knowledge, Cuvier's
fourth distinction between the animal and the
Plant has been as completely iRvalidated as the
third and second; and even the first can be re-
I Iined onS in a modified form, and subject to
receptions. Hut has the advance az biology
simply tended 10 break down old distinctions
~ ithout establishing new ones? With one quail
ii alton. the answer to this question is undoubt-
rtly in the Affirmative. The qualification comes
in view when we note the wide basis Of fact
I y the generalization that plants are essentially