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Edward Hitchcock.

The religion of geology and its connected sciences online

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infusions, so as to destroy all germs of organic life, and expelled all
the atmosphere, he attached an apparatus in such a manner that, whatever
air entered afterwards, must pass through sulphuric acid, or a solution of
potash. The result was, that no infusoria or vegetable forms appeared
during two months; but in the same infusion, placed in the open air, and
exposed to the same light and heat as that enclosed in the glass vessel,
numerous animalcula and fungi appeared in a day or two. It will need,
therefore, very long and patient experiments to establish the assertion
that galvanism alone can produce living animals without the presence of
germs.

Not many years since, the equivocal or casual production of animalcula,
without any other parentage than law, was thought to be made out by a
multitude of facts. For these minute creatures appeared almost every
where, and in places where it seemed impossible that their ova should be
found. But the researches of Ehrenberg have cleared up the difficulties of
their origination in the ordinary modes of reproduction, in nearly every
instance, and the advocates of the law hypothesis have been fairly driven
from this stronghold of their argument. In describing the various modes of
reproduction with which nature has provided the infusoria, Professor Owen
says, "Thus each leaves, by the last act of its life, the means of
perpetuating and diffusing its species by thousands of fertile germs. When
once the thickly tenanted pool is dried up, and its bottom converted into
a layer of dust, these inconceivably minute and light ova will be raised
with the dust by the first puff of wind, diffused through the atmosphere,
and may there remain long suspended; forming, perhaps, their share of the
particles which we see flickering in the sunbeam, ready to fall into any
collection of water, beaten down by every summer shower into the streams
or pools which receive or may be formed by such showers, and, by virtue of
their tenacity of life, ready to develop themselves whenever they may find
the requisite conditions of their existence. The possibility, or, rather,
the high probability, that such is the design of the oviparous generation
of the infusoria, and such the common mode of the diffusion of their ova,
renders the hypothesis of equivocal generation, which has been so
frequently invoked to explain their origin in new-formed natural or
artificial infusions, quite gratuitous." - _Lectures on Comp. Anat._ vol.
ii. p. 31.

No longer able to maintain a foothold among the animalcula, the defenders
of this hypothesis have of late attempted to take a stand among animals of
a somewhat higher grade, viz., the entozoa, or animals inhabiting other
animals. These being considerably larger than the infusoria, their ova
could not float in the atmosphere; but they possess a wonderful tenacity
of life; some of them exhibiting signs of life after having been in
boiling water for an hour; others have revived after having been packed
for a long time in ice, and frozen; others have revived after lying in a
dried state for six or seven years. Their power of reproduction, in the
ordinary modes, is also prodigious, exceeding even that of the infusoria.
It will, then, demand very strong evidence to prove that such animals
possess also the power of spontaneous production, without parentage, or
that their existence within other animals cannot be explained without such
a supposition. For, if capable of being produced without parentage, why
should such extraordinary care have been taken for their multiplication,
in almost all the ordinary modes in which animals are reproduced?

The extraordinary facts that have been discovered by Professors
Steenstrup, Owen, and others, within a few years, respecting what they
call _alternate generation_, or _parthenogenesis_, have been thought
favorable to the hypothesis of development. Among the mollusca, the
polyparia, the entozoa, and infusoria, it is found that, in some species,
the result of sexual union is the production of a larva without sex, and,
therefore, incapable of propagating in the usual way. Yet that larva can
of itself produce another larva quite different from itself, and this
larva another, and so on, sometimes for eight or ten generations, when the
spermatic force seems to be exhausted, and a progeny exactly like the
original parents that started the series is produced, capable of giving
rise to another and a similar series. Here, then, we find a succession of
progeny for several generations, and all quite unlike one another, yet
without any immediate parental agency. Why is it not an example of
spontaneous generation? and why may not new species be produced in this
manner?

There are two facts prominent on this subject which afford a full answer
to such questions. One is, that these generations of larvæ always begin
with the spermatozoon and the ovum of parents; the other is, that the
series always closes, if allowed to run its natural course, in individuals
with sex, exactly identical with those that started it; so that the
species always remains entire. The whole process is simply one of the
infinitely varied modes which nature employs to preserve and perfect the
species. The process never stops with any of the larvæ intervening between
the fertile parents at the beginning, and the fertile individuals at the
end of the series. Professor Owen supposes - certainly with much
plausibility - that some of the original germ-cells, not wanted for the
production of the first larva, pass on to form the successive generations,
till the series is complete; so that, after all, the case is not an
exception to the general law of reproduction by parental agency; and
instead of sustaining, it certainly goes against, the notion of
spontaneous generation and of transmutation of species; because it shows
how far parental influence may reach, and how tenacious nature is of
specific distinctions. For the same reasons, the case affords a
presumption against other alleged cases of equivocal generation and
metamorphoses of species.[18]

Appeal has also been made to the vegetable kingdom for examples of the
production of organic beings, viz., plants without seeds. Who has not
observed, for instance, how the clearing up and burning over of a piece of
land will often cause an entirely new tribe of plants to spring up and
flourish? Whence came the seeds? We have seen, for instance, (in Richmond,
Virginia,) a thick growth of pines upon a spot where from six to ten feet
of soil had been removed a few years previously.

It is very possible, in some cases of this kind, that the soil, having
been produced by aqueous agencies, may contain seeds to a considerable
depth, and that their vitality may have been preserved for centuries; for
we know that seeds three thousand years old, taken from Egyptian
catacombs, have germinated, in favorable circumstances. In most cases of
this sort, however, the winds have probably supplied the seed, it may be,
long before. We were one day wandering over Mount Holyoke, where a spot
recently cleared was covered with the fire-weed, a species of senecio; and
as we were musing upon its origin, a strong blast of wind swept over the
plants, just ready to throw off their seeds. Sustained by their light
egrets, they floated away on the air in numbers sufficient to cover half
the mountain with the plant, when it should be cleared and burnt over. Yet
their existence would never be suspected till those circumstances should
be developed. At least, until we can prove that the soil contains no
seeds by the most careful examination, it will be premature to infer the
equivocal production of the plants growing upon it.

Vegetable physiology furnishes another fact, which seems to me to look
still more favorable to this law hypothesis than the preceding, although
it has not been noticed, so far as I know, by the advocates of that
hypothesis. Speaking of the matter of which certain flowerless plants are
composed, Dr. Lindlay says, "It is even uncertain whether this matter will
produce its like, and whether it is not a mere representation of the vital
principle of vegetation, capable of being called into action, either as a
fungus, or algæ, or lichen, according to the particular conditions of
heat, light, and moisture, and the medium in which it is placed; producing
fungi upon dead or putrid organic beings, lichens upon living vegetables,
earth, or stones, and algæ where water is the medium in which it is
developed." Again, in speaking of that green slime which often covers the
soil, rocks, walls, and glass in damp places, he says, "The slime
resembles a layer of albumen, spread with a brush; it exfoliates in
drying, and finally becomes visible by the manner in which it colors green
or deep brown. One might call it a provisional creation, waiting to be
organized, and then assuming different forms according to the nature of
the corpuscles which penetrate it, or develop among it. It may further be
said to be the origin of two very distinct existences, the one certainly
animal, the other purely vegetable." - _Natural System_, pp. 326, 328, 334.

Now, admitting all the facts that have been detailed respecting the
production of infusoria, entozoa, acari, and cryptogamian plants to be
true, although most of them are far from being proved, it seems to me that
they do not show us how vitality is produced by mere law, without the
special agency of the Deity. Writers on the subject seem to overlook the
distinction between organization and life. The first may be present in its
highest perfection without the latter, as it is in animals and plants
recently killed. The organization is merely a preparation to receive the
mysterious principles which we call _life_ and _intellect_. Light, heat,
and electricity may be the essential agents in producing the organization,
but they do not explain the nature, or account for the presence, of life.
That must, so far as we know, come from some other and a higher source.
Galvanism may bring gelatinous matter into the form of an insect, or
infusoria, or entozoa; but there is no evidence that it can impart life,
however exquisite the organization. It may be, and we have reason to
suppose it is, the divine will to bestow life whenever a certain
organization exists; but this does not show that his special agency is not
concerned in it. He may will that the peculiar life of a lichen shall be
given to the same elementary matter which, in another situation, he
constitutes an alga, or a fungus, or even an animal. But this would not
prove that natural law alone could produce life. There is nowhere any
evidence that sensibility, contractility, and especially intellect and
volition, are the result of any natural operations. In their properties
they are so entirely diverse from all known physical effects, that we must
impute them to some other than a natural cause. We must call in the power
of a supreme intelligent Being. The laws of affinity, light, heat, and
electricity, of endosmose and exosmose, may prepare the organization, but
their power ends there; and hence true philosophy requires us to impute
the phenomena of life and intellect to an extraneous and infinitely higher
cause.

The case, then, stands thus: In ninety-nine cases out of a hundred, we
are certain that organization requires the previous existence and agency
of a being similarly organized, which we call the parent. But suppose
that, in a very few cases, the laws of nature can produce the
organization. It still demands another and a higher power - not a blind
impulse, but an intelligent cause - to bestow life and intellect. To prove
the existence of a natural cause for the arrangement of the atoms into an
organic structure, does by no means prove the same for those higher and
mysterious principles that make that structure a living, thinking being.

Such, however, are the strongest arguments by which the advocates of the
law hypothesis sustain their views of the origin of organism, life, and
intellect. The next step in their reasoning is to show how animals and
plants may be transmuted from one species, or genus, or family, to
another; so that the existing vast variety can be traced to a few original
germs. They maintain that these developments of the more from the less
perfect have proceeded along certain parallel lines; one series of
developments, for instance, taking the line of the fishes, another of the
reptiles, another of the birds, another of quadrupeds, and so on.

To prove these developments or transmutations, they appeal first to the
physiological history of the mammalian embryo. In its earliest stages, it
can hardly be distinguished, except in size, from the unborn polygastric
infusoria. The brain of a human embryo appears at first like that of an
invertebrate animal; next like that of a fish; then successively like that
of a reptile, a bird, a rodent mammal, a ruminant, and a monkey. So the
heart, at an early stage, looks like that of an insect; then it has two
chambers, like that of a fish; then it becomes three chambered, like that
of a reptile; and finally, four chambered, as in the mammalia. The
inference which these theorists would draw from such facts is, that man
actually begins his existence as an animalcule, and passes successively
through the mould or condition of other animals, before he reaches the
highest. And the reasons why he does become a man, rather than an
echinoderm, or a fish, or a monkey, is only some slightly modifying
circumstance, as, for instance, a longer gestation. It appears to me,
however, that the inferences sound philosophy should derive from such
facts are, first, that, while there is a seeming resemblance between the
human embryo and that of lower animals, there is, in fact, a real and a
wide diversity; so that the one infallibly becomes an inferior animal, and
the other a man. Could a single example be produced in which a human
embryo stopped at and became an insect, or a fish, or a monkey, there
might be some plausibility in the supposition. But it is as certain to
become a man as the sun is to rise and set; and, therefore, the human
condition results from laws as fixed as those that regulate the movements
of the heavenly bodies. That is a very superficial philosophy which infers
identity of nature from mere external resemblance.

The phenomena of hybridity furnish another ground of argument in favor of
the transmutation of species, and of course in favor of the law
hypothesis; for that hybrids are sometimes the result of the union of
different species will not be denied. There is, however, a natural
repugnance to union between different species; and in a state of nature
this can very rarely be overcome. But domestication changes and almost
obliterates many natural instincts, and hence hybridity is far more common
among domesticated animals and plants. As a general fact, also, the hybrid
offspring is incapable of propagating its own race, without union with one
of the original species by which it was produced; and this inability to
continue this mixed race has been generally regarded among naturalists as
the best characteristic of species. Some, however, attempt to show that
some hybrid races do continue from generation to generation to propagate
their kind. But in most cases the hybrid race ere long runs out, and there
is always a strong tendency to revert to the original stock; and were it
not for the influence of man, probably such a thing as hybridity would
scarcely ever have been heard of. Nature seems to have established strong
barriers around species, so that an identity should be preserved; and even
if we admit the possibility of their coalescence in some cases, yet we
have evidence that almost always they are preserved distinct from century
to century; and the same is true even of the more prominent varieties, for
we find not only the same species, but the same varieties of animals and
plants, preserved some three thousand years in the Egyptian catacombs,
that are now alive in the same country. How idle, then, to suppose that
the laws of hybridity will account for such radical and entire
transmutations as this hypothesis supposes! To accomplish this, it would
need as strong a tendency in nature to a union of species, genera, and
families, as now exists against it.

But a special appeal has been made on this subject to geology. The history
of organic remains, it is thought, corresponds to what we might expect, if
the hypothesis of development is true. In the oldest rocks we find chiefly
the more simple invertebrate animals, and the vertebrated tribes appear at
first in the form of fish, then of reptiles, then of birds, then of
mammals, and last of all of man. What better confirmation could we wish
than this gradually expanding series? True, all the great classes of
organic beings, vegetable and animal, are found nearly at the earliest
epoch, and continue through the entire series of rocks. But we have only
to suppose a distinct stirps for each of the classes, and that the
developments took place along parallel lines, in order to harmonize the
facts with the hypothesis.

Such a general view of the subject of organic remains seems to give
plausibility to the hypothesis of organic development. But the tables are
turned when we descend to particulars. The idea of a distinct stirps or
germ for each great class of animals and plants seems to me to destroy an
essential feature of the hypothesis. It supposes that law produces at once
a vertebral animal and a flowering plant; for the first, certainly, we
find in the very lowest of the fossiliferous rocks. "The lower silurian,"
says Sir Roderick Murchison, in 1847, "is no longer to be viewed as an
invertebrate period, for the onchus (a genus of fish) has been found in
the Llandeilo Flags, and in the lower silurian rocks of Bala."

It is also a most important fact, that this fish of the oldest rock was
not, as the development scheme would require, of a low organization, but
quite high on the scale of fishes. The same is true of all the earliest
species of this class. "All our most ancient fossil fishes," says
Professor Sedgwick, "belong to a high organic type; and the very oldest
species that are well determined fall naturally into an order of fishes
which Owen and Müller place, not at the bottom, but at the top of the
whole class." - _Discourse on the Studies of the University_, &c. 5th edit.
p. lxiv. pref.

This point has been fully and ably discussed by Hugh Miller, Esq., in his
late work, "The Footprints of the Creator, or the Asterolepis of
Stromness." The asterolepis was one of these fishes found in the old red
sandstone, sometimes over twenty feet long; yet, says Mr. Miller, "instead
of being, as the development hypothesis would require, a fish low in its
organization, it seems to have ranged on the level of the highest
ichthyic-reptilian families ever called into existence."

Another point which Mr. Miller has labored hard to establish, and of which
there seems to be no reasonable doubt, is, that in many families of
animals, not only were the first species that appeared of high
organization, but there was a gradual degradation among those that were
created afterwards. Of the fishes generally, he says, that "the progress
of the race, as a whole, though it still retains not a few of the higher
forms, has been a progress, not of development from the low to the high,
but of degradation from the high to the low." Again he says, "We know, as
geologists, that the dynasty of the fish was succeeded by that of the
reptile; that the dynasty of the reptile was succeeded by that of the
mammiferous quadruped; and that the dynasty of the mammiferous quadruped
was succeeded by that of man, as man now exists - a creature of a mixed
character, and subject, in all conditions, to wide alternations of
enjoyment and suffering. We know further, - so far, at least, as we have
succeeded in deciphering the record, - that the several dynasties were
introduced, not in their lower, but in their higher forms; that, in short,
in the imposing programme of creation, it was arranged as a general rule,
that in each of the great divisions of the procession the magnates should
walk first. We recognize yet further the fact of degradation specially
exemplified in the fish and the reptile." "Among these degraded races,
that of the footless serpent, which _goeth upon its belly_, has long been
noted by the theologian as a race typical, in its condition and nature, of
an order of hopelessly degraded beings, borne down to the dust by a
clinging curse; and curiously enough, when the first comparative
anatomists in the world give _their_ readiest and most prominent instance
of degradation among the divisions of the natural world, it is this very
order of footless reptiles that they select."

Among the invertebrate animals are numerous examples of the deterioration
of a race. M. Alcide D'Orbigny, one of the most accomplished of living
paleontologists, in his _Cours Elementaire de Paleontologie et de
Geologie_, speaks as follows of the cephalopods found in the oldest rocks:
"See, then, the result; the cephalopods, the most perfect of the mollusks,
which lived in the early period of the world, show a progress of
degradation in their generic forms. We insist on this fact relative to the
cephalopods, which we shall hereafter compare with the less perfect
classes of mollusks, since it must lead to the conclusion that the
mollusks, as to their classes, have certainly retrograded from the
compound to the simple, or from the more to the less perfect."

Such facts as these are absolutely fatal to the hypothesis of development;
and geology abounds with them. Indeed, through all her archives, we search
in vain for facts that show any thing like a passage of one species,
genus, or family, into another. Certain distinct types characterize the
different formations up to a certain period, when there is a sudden
change; and in the subsequent strata we find animals and plants entirely
different from those that have disappeared. The new races are, indeed,
often of a higher grade than those that preceded them, but could not have
sprung from them.

The true theory of animal and vegetable existence on our globe appears to
be this: Such natures were placed upon the earth as were adapted to its
varying condition. When the earliest group was created, such were the
climate, the atmosphere, the waters, and the means of subsistence, that
the lower tribes were best adapted to the condition of things. That group
occupied the earth till such changes had occurred as to make it unsuited
to their natures, and consequently they died out, and new races were
brought in; not by mere law, but by divine benevolence, power, and wisdom.
These tribes also passed away, when the condition of things was so changed
as to be uncongenial to their natures, to give place to a third group, and
these again to a fourth, and so on to the present races, which, in their
turn, perhaps, are destined to become extinct. From the first, however,
the changes which the earth has undergone, as to temperature, soil, and
climate, have been an improvement of its condition; so that each
successive group of animals and plants could be more and more complicated
and perfect; and therefore we find an increase and development of
flowering plants and vertebral animals. And yet, from the beginning, all
the great classes seem to have existed, so that the changes have been only
in the proportion of the more and less perfect at different periods. In
short, we have only to suppose that the Creator exactly adapted organic
natures to the several geological periods, and we perfectly explain the
phenomena of organic remains. But the doctrine of development by law
corresponds only in a loose and general way to the facts, and cannot be
reconciled to the details. If that hypothesis cannot get a better foothold
somewhere else, it will soon find its way into the limbo of things
abortive and forgotten.

I have now noticed, I believe, the principal sources of evidence in which
the law hypothesis rests; and at the best, we find only a possibility, but
rarely, if ever, a probability, that such a power exists in nature. I turn
now, for a few moments, to the arguments on the other side; that is,
against the hypothesis.

_And first, it cannot explain the wonderful adaptation of animals and
plants to their condition and to one another._

There is not a more striking thing in nature than that adaptation; and
geology shows us that it has always been so. Now, if any thing requires
the exercise of infinite wisdom and power, it is this feature of creation.



Online LibraryEdward HitchcockThe religion of geology and its connected sciences → online text (page 24 of 39)