The sun. [volume] (New York [N.Y.]) 1833-1916, 1879-06-15


collateral branches. we are brought to the gas
traed in which we recognize the simplest con-
coivable prototype Of an animal with two germ
layers. The gastraea itself must have oriRi-
mated from among those rudimentary animate
forms embraced under the name OF primitive
beings tprOt0Sod). among which the variety
possessing most interest for US is the one called
mnGJd. whose peculiar significance depends
on its resemblance to tho human egg cell. Here
We have reached tho lowest OF those impreR-
nable points at which the value OF Haeckers
fundamental law Is demonstrated. and where.
from the earliest embryonic stage. we can d.
rectly infer the remotcst parent form. The
amrboid nature Of the young egg cell in which
each man begins his individual existence iust-
nes us in affirming that the oldest ancestors of
the human race. as, indeed. Of the whole animal
kingdom. we're simple ampboid cells. Here
arises another question-whence. in the begin
ming OF the organic history OF the oarth. camo
the earliest amube7 According to Haeckel.
these one-celled organisms can only have been
originally developed from tho simplest OF vital
entities. the mOnei'on. whose body has no definite
shape and is but particle Of primitive slime.
q little mass Of living abumen. performing.
however, the essential functions OF life, and
everywhere met with as the material basis Of
animate existence. This step accomplished
Prof Hacckel is brought to the last or. perhaps
we should rather call It the first problem In tho
history Of evolution. viz. the question OF spon-
taneous generation.
In the definite limited sense In which Prof.
Haeckel maintains Spontaneous generation.
and assumes IL as a necessary hypothesis TO eN-
plain the first beginning Of life upon tho earth.
II merely implies the origin Of monera-that 10.
OF structuroless organisms without organs
I'm ia
head there is a great deal OF absurd misconcep-
tion. 1t has been repeatedly acknowledged by
English and German scientists that every differ
entiated organism. every vital entity composed
OF organs, can only have originated from an
undifferentated lower organism by differ
entiation Of its parts. Hence we need not as
sumo the process of spontaneous generation.
even In the production OF tho simplest
subdivisions in tho case OF the single cell.
viz. tho nucleus and the outer cell substance.
OF protoplasm. But he holds that investigators
OF nature. II they would not have recourse ut
the end Of n chain to the assumption Of a super
natural miracle refuted al each preceding link.
are bound to seek natural explanation Of tho
origin Of life This postulatc is required. he
thinks by tho demand OF the human under
standing for causaity. 1t is fortified. too. by an
overwhelming argument from analogy. when
we reflect. on the one hand. that the whole
inorganic history Of the earth proceeds in ac-
cordance with mechanical laws. and without
any Intervention by creative power. and when,
on the other hand. we consider that tho entire
organic history OF the world Is also determined
by similar mechanical laws, no supernatural
Interference by creative power being needed
for the production Of the various organisms
Why. then. at one stop should we affirm that
for which animated nature nowhere else
affords warrant. to wit. miracle? Prof
Haeckel's own opinion Is that the oldest
monera were engendercd In the sea by spon-
taneous generation. just rs crystals form
in the matrix. In other words. when ami
mated bodies FIRST appeared on our planet.
there must at the outset nave been formed. by n
process purely chemical. from purely inorganic
carbon combinations. that very complex nj
troGenized carbon compound. which we call
plassson or primitive slime" and which Is
the oldest material substance In which vital
activities are combined. Such is the doctrine
OF spontaneous generation within tho narrow
limits defined by Haecksl. IL cannot DO expert
mentally refuted. Each experiment with a
negative result merely proves that under the
conditions always very artificial. supplied by
us. no organism has as yet been produced to
order and by design from Inorganic constitu-
uents But II man out OF carbon and nitrogen
has never made bit Of protopasm. neither has
he out OF carbon produced diamond. Neither
can Haeckel's theory. on the other hand. be- ex-
permentally proved unless great difficulties
are overcome since. even II In our own time
monera were produced daily by spontaneous
genernton-as II IL possible they are in the
lowest depths Of the ocean-it would be ex-
tremey hard. almost improbable. to furnish
absolute empire proof OF the phenomenon.
/ There remains. however the argument from
analogy and harmony. whose weight. OF course.
must vary with the weight ard exactness Of a
students knowledge. Obviously il must be re-
iected and tue course OF nature rudely disio-
Gated by those who choose to postulate mira
Gle ut the birthpoint Of protoplasm.
Wa shall mark but briefly the earlier steps In
| the descent Of tho human species. although the
whole process OF evolution is traced by Prot
Hacckel in much detail. In order, however
to dwell at more length on his dennition OF
mans precise position in the suborder OF
catarhine or narrow-nosed apes we shall
pass cursorily over tho preceding stages Of
development. We repeat. therefore. that the
first and most important OF ontogenotic facts
| IL, that every man. like every other animal is
ut the commencement OF his individual ex.
istence. simple coll from this cell pro.
coeds. by repeated division. u many-cciled
body. the so-called mulberry germ. presently
changed into cup germ, and this again
into an intestinal germ vesicle. The two dis
tinct cell strata. which compose the wall OF the
latter. are the two primary germ layers. the
skin layer. namely, and the intestinal layer
By following the germ history Of the two
layered germ still further wa find tina
by nssion are produced four secondary
layers which have the same constitu
ton and eenetc significance in man NJ
in all other vertebrates. In other words. tn,
manner after which. from these four secondary
germ layers. arc developed the various organi'
systems embracing the skin. the nerves. thu
kidneys. the mucous membrane and the or
gans OF motion is Just the same throughout tn
scale Of vertebrate existence. Within this grea
animal tribe. however. Prof. Haeekel traces tn
further progression which takes place in the on
tire body. rs well as In its several parts an,
functions and points out that the human EN-
bryo exhibits this higher development in tn
form peculiar TO mammals. We are shown
finally. that even within tho latter category
the various stages Of tribal evolution which dc
termined the classification OF mammals cor
respond throughout to the gradatons OF en-
bryonic formation through which the huma
germ passes In Il later period OF its pre-nata
existence. We are thus enabled to fix tn
place Of man more definitely in tn