_epiphyses_, one for the _coracoid_ process, one for the _acromion_, and
one for the lower angle of the bone, the ossification of which begins
soon after puberty, their union with the body of the bone taking place
between the ages of twenty-two and twenty-five years. The _clavicle_ has
an _epiphysis_ at its sternal end, which begins to form between the
eighteenth and twentieth years, and is united to the rest of the bone a
few years later. The consolidation of the shoulder-bone (_humerus_) is
completed rather earlier; the large piece at the upper end, which is
formed by the coalescence of the ossific centres of the head and two
tuberosities, unites with the shaft at about the twentieth year; whilst
its lower extremity is completed by the junction of the external
condyle, and of the two parts of the articulating surface (previously
united with each other), at about the seventeenth year, and by that of
the internal condyle in the year following. The superior _epiphyses_ of
the arm-bones (_radius_ and _ulna_) unite with their respective shafts
at about the age of puberty; the inferior, which are of larger size, at
about the twentieth year. The _epiphyses_ of the _metacarpal_ and
_phalangeal bones_ (those of the hand and fingers) are united to their
principals at about the twentieth year. In the _Lower Extremities_, the
process of ossification is completed at nearly the same periods as that
of the corresponding parts of the Upper. The consolidation of the
hipbones (_ilium_, _ischium_, and _pubis_) to form the _os innominatum_,
by the ossification of the triradiate cartilage that intervenes between
them in the socket of the thigh (_acetabulum_), does not take place
until after the period of puberty; and at this time additional
_epiphyses_ begin to make their appearance on the crest of the _ilium_,
on its anterior inferior spine, on the tuberosity of the _ischium_, and
on the inner margin of the _pubes_, which are not finally joined to the
bone until about the twenty-fifth year.[88]
The concurrence of these conditions in the skeleton, the nearly balanced
ratio of the bloods, the perfected dentition, the beard, the deepened
voice, the prominent larynx, and the stature, combine to point out,
with infallible precision, the age of this Man, as between twenty-five
and thirty years.
So far, then, we can with certainty trace back the history of this
being, as an independent organism; but did his history then commence? O
no; we can carry him much farther back than this. What means this
curious depression in the centre of the abdomen, and the corrugated knob
which occupies the cavity?[89]
This is the NAVEL. The corrugation is the cicatrice left where once was
attached the umbilical cord, and whence its remains, having died,
sloughed away. This organ introduces us to the foetal life of Man;
for it was the link of connexion between, the unborn infant and the
parent; the channel, through whose arteries and veins the oxygenated and
the effete blood passed to and from the parental system, when as yet the
unused lungs had not received one breath of vital air.
And thus the life of the individual Man before us passes, by a necessary
retrogression, back to the life of another individual, from whose
substance his own substance was formed by gemmation; one of the
component cells of whose structure was the primordial cell, from which
have been developed successively all the cells which now make up his
mature and perfect organism.
* * * * *
How is it possible to avoid this conclusion? Has not the physiologist
irrefragable grounds for it, founded on universal experience? Has not
observation abundantly shown, that, wherever the bones, flesh, blood,
teeth, nails, hair of man exist, the aggregate body has passed through
stages exactly correspondent to those alluded to above, and has
originated in the uterus of a mother, its foetal life being, so to
speak, a budding out of hers? Has the combined experience of mankind
ever seen a solitary exception to this law? How, then, can we refuse the
concession that, in the individual before us, in whom we find all the
phenomena that we are accustomed to associate with adult Man, repeated
in the most exact verisimilitude, without a single flaw--how, I say, can
we hesitate to assert that such was his origin too?
And yet, in order to assert it, we must be prepared to adopt the old
Pagan doctrine of the eternity of matter; _ex nihilo nihil fit_. But
those with whom I argue are precluded from this, by my first Postulate.
XI.
PARALLELS AND PRECEDENTS.
(_Germs._)
"Every cell, like every individual Plant or Animal, is the
product of a previous organism of the same kind."--(DR.
CARPENTER, _Comp. Physiol._ Sec. 347.)
In the preceding examples I have assumed that every organic entity was
created in that stage of its being which constitutes the acme of its
peculiar development; when all its faculties are in their highest
perfection, and when it is best fitted to reproduce its own image. From
the very nature of things I judge that this was the actual fact;[90]
since, if we suppose the formation of the primitive creatures in an
undeveloped or infant condition, a period would require to lapse before
the increase of the species could begin; which time would be wasted. To
those, indeed, who receive as authority the testimony of the Holy
Scripture, the matter stands on more than probable ground; for its
statements, as to the condition of the things created, are clear and
full: they were not seeds, and germs, and eggs, and embryos,--but "the
tree yielding fruit whose seed was in itself,"--"great whales,"--"winged
fowl,"--"the beast of the earth,"--and "man."[91]
But I do not mean to shield myself behind authority. I have begged the
_fact_ of creation; but not the truth, nor even the existence, of any
historic document describing it. It is essential to my argument that any
such be left entirely out of the question; and, for the present, I
accordingly ignore the Bible.
It is possible that some opponent may object to my assumption of
maturity in created organisms.
"Your deductions may be sound enough," such an one may say, "provided
your newly-created Locust-tree had so many concentric cylinders of
timber, your Tree-fern had a well-developed stem of leaf-bases, your
Coral a great aggregation of polype-cells, your Tortoise a carapace of
many-laminated plates, your Elephant a half-worn set of molars, and your
Man a thoroughly ossified skeleton. But how do you know that either of
these organisms was created in this mature stage? I will not deny that
each was created,--was called suddenly out of non-entity into entity;
but I believe, or at least I choose to believe,--that each was created
in the simplest form in which it can exist; as the seed, the gemmule,
the ovum, the--ahem!"
Pray go on! you were about to say "the infant," or "the foetus," or
"the embryo," probably; pray make your selection: which will you say?
"Well, I hardly know. Because, if I choose the new-born infant, you will
say, Its condition implies a nine months' pre-existence, certainly; not
to speak of the absurdity of a new-born infant being cast out into an
open world without a parent to feed it. If I say, The foetus, or the
still more incipient embryo, I involve, at once, a pre-existent mother.
I am afraid you have me there!"
I think I have. However, let us take up the matter orderly, and proceed
on the supposition that my previous examples must be all cancelled, and
the question argued _de novo_, on the assumption that each organism was
created in its least developed condition.
It will not be considered necessary, I suppose, to look at any
intermediate condition of the organisms. The argument which is based
upon the leaf-scales of the Fern or the Palm would essentially apply to
either of these plants when it first issues from the ground. At the
period when it comprises but a single frond, the botanist would no more
hesitate in pronouncing that the organism had passed through stages
previous to that one, than he would when it possesses an elongated
stipe; though, in the latter case, the evidences of the pre-existence
are more patent to the uninstructed eye. He would say, The single frond
implies, with absolute necessity, a spore in the one case, a seed in the
other; and we need not to see either, to be assured that this must have
preceded the leaf-stage.
But you go farther back still. "The plant was created as a seed." Let us
renew our imaginary tour at the epoch, or epochs (as many as you
please), of creation, on this supposition.
Here is a very young plant of the curious Seychelles Palm or Double
Cocoa-nut (_Lodoicea Sechellarum_). A single frond is all that is yet
developed, and this is as yet unexpanded, the pinnae being still folded
on the midrib, like a fan. Trace the frond down to its base. It springs
from a thick horizontal cylindric process, which has also shot down a
radicle into the soil. We trace the cylindrical stem along the surface
of the soil, and find, lying on the ground, among the grass, but not
buried, a great double nut, something like the two hemispheres of a
human brain, or like a common cocoa-nut, half split open and healed. Out
of this the thick stem has issued; and we find that it is only the
cotyledon of the seed, that has prolonged its base in the process of
germination, in order to throw up, clear of the nut, the plumule and
radicle.
We look at the great nut, and find, on the woody exterior of the fibrous
pericarp, at the side opposite to that whence issues the cotyledon, a
broad scar. What is this? It is the _mark left by the severance of a
footstalk_, which united the fruit to the parent plant. This great drupe
was once a small ovary seated in the centre of a three-petaled flower,
which, with many others, issued out of a great spathe, a mass of
inflorescence, and hung down from the base of the leafy coronal of an
adult palm-tree. This scar is an irreproachable witness of the existence
of the parent palm.
Here, lying on the dry and dusty earth, is a brown flat bean of great
hardness. This is a seed destined by and by to produce that splendid
tree _Erythrina crista-galli_. But it has been just created.
This bean bears on one of its edges an oval scar, very distinctly
marked, called the _hilum_. This was the point of attachment of a short
column, by which the seed was united to one of the sutures of a long
pod, in the interior of which it lay, in company with several others
like itself. This great legume or pod had been the bottom of the pistil
of a papilionaceous flower, crowned by a tiny stigma, lodged in a sheath
formed by the united stamens, and surrounded by a corolla of refulgent
scarlet petals.
Of course such a flower was not an independent organism; it was one of
many that adorned a great tree, the history of whose life would carry us
back through several generations of human years.
[Illustration: GARDEN TULIP.
Fig. 1. A flower with two petals removed, to show the ovary, _a_. Fig.
2. The same ovary, more mature, divided longitudinally; _b_, the unripe
seeds, packed on each other; _c_, a portion of the same carpel, from
which the seeds have been removed.]
This single infolding leaf, that is just shooting from the soil, so
small and feeble,--what of this? There are certainly no concentric
cylinders of timber here: can we trace a previous history of this?
Yes: by carefully removing the soil from the base, we see that it
originates in a flat yellow seed--the seed of a Tulip. Here again we
have no difficulty in detecting evidence of its former attachment. A
great number of these seeds were once closely packed one on another, in
each of the three carpels that constituted the capsule. And this capsule
had been the oblong, three-sided ovary, which formed the body of the
pistil in some beautiful Tulip.
Do you observe these two round fleshy leaves, just peeping from the
sandy earth? They are the earliest growths of a plant of _Arachis
hypogaea_. In this case again, to understand the true relations of this
organism, we must expose it wholly to view.
Beneath the surface of the earth, then, I find that these seed-leaves
are the two halves (_cotyledons_) of a kind of pea, which was formerly
enclosed in a wrinkled skinny pod. But what is most interesting is that
the pod is here, the cotyledons shooting out of it. And, attached to
one end of the pod, here is a slender stalk, now withered and dry, which
projects out of the ground into the air.
[Illustration: GERMINATION OF EARTH-PEA.]
Now here we have a beautiful link of connexion with the past. The plant
before us does not ripen its seeds, and then drop them to care for
themselves, as most plants do. "The young fruit, instead of being placed
at the bottom of the calyx, as in other kinds of pulse, is found at the
bottom and in the inside of a long slender tube, which looks like a
flower-stalk. When the flower has withered, and the young fruit is
fertilized, nothing but the bottom of the tube with its contents
remains. At this period a small point projects from the summit of the
young fruit, and gradually elongates, curving downwards towards the
earth. At the same time the stalk of the fruit lengthens, until the
small point strikes the earth, into which the now half-grown fruit is
speedily forced, and where it finally ripens in what would seem a most
unnatural position."[92]
The young plant before us has been this moment created, and created in
this incipient stage of growth: and yet there is, even here, an
indubitable evidence, so far as physical phenomena can afford it, of a
past history. It would be utterly impossible to select any stage in the
life of the Earth-pea, which did not connect itself, visibly and
palpably, with a previous stage.
Let us return to the shore-loving Mangrove. You object to my assumption
that it was created as a tree, with a well-branched stem elevated upon
a series of arching roots; and to my deduction of pre-lapsed years for
the formation of those roots. Very well. I give it up. You allow that
the primitive Mangrove was created in some stage, but you contend for
the germ-stage, the simplest condition of the plant, whatever that might
be.
Now, where shall we find it? In the first pair of developed leaves? They
certainly point back to the cotyledons. To the cotyledons, then, let us
look.
Lo! the young plant is germinating before its connexion with the parent
is severed. It is the singular habit of this tree, that its seeds are
already in a growing condition, while they hang from the twig. Each seed
is a long club-shaped body, with a bulbous base and a slender point,
more or less produced. While it yet hangs from the branch, the radicle
and crown of the root begin to grow, and gradually lengthen, until the
tip reaches the soil, which it penetrates and thus roots itself; while
those which depend from the higher branches, after growing for a while,
drop, and, sticking in the mud, throw out roots from one end, and leaves
from the other.
[Illustration: SEED OF MANGROVE.]
What have you gained, then, in this case, by going back to the germ? The
germ as decisively asserts its origination from an already existing
organism--the parent tree--as the flourishing tree witnesses its gradual
development from a germ. The Mangrove could not by possibility have been
created in any stage, consistent with the identity of the species with
that which we behold now in the nineteenth century,--that did not show
ocular evidence of a previous history;--evidence from the nature of
things fallacious.
It would be merely tiresome to go on through the vegetable kingdom. In
every plant the simplest condition--viz. that of a spore or
seed--depends on some development, or process, or series of processes,
that have preceded it. Nor does the lapse of time between the previous
process and the apparent result at all destroy their necessary
connexion. In the case of the curious Misseltoes, the ovule does not
appear till three months after the pollen has been shed; but when it
does appear, its existence as an organism capable of developing the
characteristic form of its species, is as truly dependent on the
previous existence of the pollen, as if not an hour had intervened.
Supposing the essential conditions of vegetable organisms to have been
at the first what they are now; in other words, supposing specific
identity to have been always maintained,--which I have demanded as a
postulate for this argument,--it appears to me demonstrable, that every
plant in the world presented at the moment of its creation evidences
_prochronic_ development, in nowise to be distinguished from those on
which we firmly rely as proving the lapse of time.
But is the case otherwise in the animal world?
We traced back the history of our Medusa through its marvellous series
of gemmative developments, till we reached the minute Infusory-like
gemmule, which is its simplest form. Now it is quite legitimate to
assume that _this_, and not the pulmonigrade umbrelliform stage, was the
one in which the new-created Medusa began existence. Have we, then, got
rid of the evidence of past time, which we deduced from the successive
changes through which the adult had passed? What is this ciliated
planule, and whence comes it? It is the embryo discharged from the
fringed ovary of a female Medusa; it has already passed through several
changes of colour and form. It is now of a deep yellow colour; it has
been violet; it has been colourless: it is now shaped like a dumb-bell;
it was a globule; it had been a mulberry-mass. Yet earlier, it had been
a component cell of the ovarian band, which divided the generative
cavity from that of the stomach, in the parent Medusa.
In like manner the ciliated gemmule from which was formed the "pluteus"
of the Urchin, was dependent on the existence of a parent Urchin; the
monadiform germ from which was developed the pentacrinus of the
Feather-star, was originally hidden in the ovarian tubes of a parent
Feather-Star: the infant _Serpula_ that deposited the first atoms of
calcareous matter as a commenced tube, had begun its own existence in
the body of a parent _Serpula_.
It is true the evidence of the connexion between the germ and the
parent is not in these low forms always patent to the eye; it is
physiological. But it is not less conclusive to one who is able to
appreciate its force. A physiologist is as sure that every germ, every
ovum, in the Invertebrate animals, was produced by an animal of a former
generation, as he is of the same fact in a Mammal, where his eye can see
the scar of the umbilical cord.
In many instances there is stronger, or rather more obvious and
ordinarily appreciable, evidence of the link between the present and the
past generation, than the physiological dependence. The world of
Insects, which, from its immensity, and from the high organic rank of
its members, affords us so exhaustless a mine of economical wonders,--is
rich in examples to the point. A few of these I shall cite.
The eggs of many Insects are not dropped anywhere, at random; for, as
the newly-born young have limited powers of locomotion, and yet are in
general able to subsist only on some particular kind of food, it is
necessary that their birth should occur in the immediate proximity of
such food: and therefore that the egg should be so placed. Now this
circumstance would not be specially noteworthy if the locality selected
for the deposition of the egg were the same as that in which the parent
insect had been accustomed to find its own private enjoyments: we should
reasonably say that the eggs were placed here, because the parents
happened to be here. The case, however, is very different.
We never find the egg of the Peacock Butterfly adhering to the leaf of a
cabbage, nor that of the Garden White to the leaf of a nettle; but the
nettle is invariably selected for the former, and a cruciferous plant
for the latter.
Yet there is nothing in the individual wants or likings of the
Butterfly, in either case, to account for this. Both the one and the
other flutter through the sunny air, alight to drink the water of some
slushy pool, rest on the expanding flowers and probe them for nectar, or
suck the exuding juices of an over-ripe fruit. But when did you ever see
the gorgeous-eyed Peacock feeding on a nettle, or the White on a
cabbage? Eagerly as they seek these plants, it is solely for the purpose
of depositing their eggs where instinct teaches them their unborn
progeny will find suitable food.
Supposing, therefore, we had found the egg of either of these
butterflies at the moment of its creation, we should assuredly have
found it on the nettle or the cabbage (as the case might be); because to
suppose it in any other situation would be equivalent to supposing it so
placed as that the end of its creation--the life of the species
created--would be _ipso facto_ frustrated. But, finding it so, the
question naturally arises,--Why here, and not elsewhere? and the only
possible answer, on the ground of phenomena, is, Because the parent
chose this situation for it. And thus we are inevitably thrown back to
an anterior generation, which is equivalent to past time.
Again, if we had seen the egg of the Nut Weevil (_Balaninus nucum_) just
come from the creative hand of God, we should certainly have found it
within the immature soft-shelled hazel-nut, because there alone would
the grub when hatched meet with "food convenient for" it. And yet if we
had sought (ignorant of the fact of its recent creation) the reason of
its being there, our acquaintance with entomology would have pointed to
the parent beetle, who, with her jaws placed at the tip of a long
slender snout, had bored a tiny hole in the tender shell, and had then
projected the egg from her abdomen into the interior.
The eggs of the _Oestridae_--for example, the Worble of the Ox
(_Oestrus bovis_) or the Bot of the Sheep (_Oe. ovis_)--would be
discovered in no other circumstances than beneath the skin of the
former, and at the edge of the nostrils of the latter. For these are the
respective situations in which the egg is always deposited, that of the
Worble hatching _in situ_, and forming a superficial abscess in
communication with the external air, and that of the Sheep-bot producing
a larva which crawls up the nostrils of the poor animal, till it finds a
suitable resting-place in the frontal sinuses of the skull. To suppose
the egg in any other circumstances than those which I have mentioned,
would be to consign it to certain destruction. Yet does not its presence
there bear witness to the eclectic care of the parent Gadfly, whose
unerring instinct knew how to seek and select the right position?
If you had set yourself to look for the egg of a _Pimpla manifestator_,
a common Cuckoo-fly, where would you have looked for it, but in the
fatty tissues of a wild bee's grub, that was lodged in a deep hole in
some old post? If you had sought elsewhere, you would surely have been
disappointed. And would not its presence there bear testimony to the
lengthened ovipositor of the well-known brisk and busy fly, and to its
remarkable habits?[93]
The grub of the Pill Chafer or Tumble-dung Beetle (_Phanaeus_) feeds on
the ordure of _Mammalia_. And, in order that the newly-hatched young may
have a copious supply of food at hand, the parent chafer with its jaws
detaches a mass of recent ordure, which it then rolls over the ground
with its hind feet, until it acquires a globular form, and a coating of
earth or sand. An egg is then deposited in the centre of the ball, which
is rolled into a hole made in the earth to receive it. The coating of
earth drying and hardening, keeps the interior of the mass fresh and
moist until the young grub is hatched, when it at once begins to devour
its savoury and delicate provision.
It would be vain to search for the egg of a _Cynips_ except within a
vegetable gall, or at least within the tissues of a plant that are going
to produce one. Take as an example _C. quercus_, which produces the
spongy excrescence well known as the common Oak-apple. The female
Gall-fly is furnished with an ovipositor in the shape of a very fine
curved needle, with which she punctures the tender bark of an oak shoot,
lodging an egg in the perforation. Stimulated by some fluid, probably,
which is poured into the wound at the same time, the sap forms a
peculiar tissue around the egg, swelling into a large ball, on which the
young grub begins to feed eagerly, and in which it finds the only
nutriment on which it could subsist.
Now, if we had found the egg of a Gall-fly newly created, we should
certainly have found it in a gall; and the gall would have afforded us
indubitable evidence of the wounding of the vegetable tissues, and of
the organ, secretion, and instinct of the tiny fly by which the process
had been effected. The evidence would be irresistible, but of course it
would be fallacious.
Let us now look at a few examples in which the egg is found in
invariable association not merely with something that the parent has
found for it, but with something that has proceeded from her, a part of
herself.