take on some changes afterward. Haeckel says: "Every primitive egg being
an entirely simple, somewhat round, moving, naked cell, possesses no
membrane, and consists only of a nucleus and protoplasm. These two parts
have long borne distinctive names: the protoplasm being called the
_vitellus_, or yelk, and the nucleus the _germinal vesicle_ (_vesicula
germinativa_)." The same author also says: "The human egg cannot be
distinguished from that of most other mammals, either in its immature or
in its more complete condition. Its form, its size, its composition, are
approximately the same in all. In its fully developed condition it has
an average diameter of one-tenth of a line--about the one hundred and
twentieth part of an inch. If the mammalian egg is properly isolated,
and held on a plate of glass towards the light, it appears to the eye as
a very fine point. The normal eggs of most of the higher mammals are of
almost exactly the same size. They have the same spherical form; always
the same characteristic covering; always the same clear, round germinal
vesicle with its dark germinal spot. Even under the highest power of our
best microscopes there _appears_ to be no essential difference between
the eggs of a human being and that of the ape, the dog, the cat or other
animal." This similarity is one of appearance only. There is a
difference, and of this I shall speak later. It may be asked if the egg
of a bird is the same as the egg of a mammal. The mature bird's egg, as
it is laid in the nest, differs materially from that of any mammal; but
in its miniature form, as found in the hen's ovary, it is also the same.
The egg of a bird after it leaves the ovary, and as it passes along the
oviduct, takes on secretions in its passage which it converts into yelk,
and afterwards a shell is added to give it protection in the external
world, where it must undergo incubation before it can become a bird; but
before it takes on its shell it has been fertilized, and this also
causes other changes. Haeckel says: "After the ripe egg of the bird has
left the ovary, and has been fertilized in the oviduct, it surrounds
itself with various coverings which are secreted from the inner surface
of the oviduct. The thick layer of transparent albumen first forms round
the yellow yelk; this is followed by the formation of the outer
calcareous shell, within which is another envelope, or skin. All these
coverings and additions which are gradually formed round the egg are of
no importance to the development of the embryo; they are parts which
have nothing to do with the simple egg cell. Even in the case of other
animals we often find large eggs with thick coverings. For example, the
shark's; but even in this case the egg is originally exactly similar to
those of mammals when in its primitive condition as it comes from the
ovary. In the case of the bird these additions serve only as food for
the growing embryo, which, in the case of mammals, is furnished by a
stream of the mother's blood, making 'stored-up' nutriment unnecessary."
Before, however, we can have _true germ plasm_ the mother cell must be
fertilized by the male cell. This is true of all the higher plants and
animals. There are some low plants and animals in which fertilization by
the male cell is not required. This has been called virginal generation.
In no mammal is this possible.
How fertilization takes place and what it signifies are both important
questions which have not been entirely settled, and it almost seems as
if they could not be settled in some of their details, except in the
lower forms of life. Nature has so protected the process from
observation in the higher animals that it cannot be studied in detail;
but in plants and the lowest animals it has been observed with some
success, and we may infer that the process is very much the same in the
higher animals.
Haeckel, in his great work on the Evolution of Man, tells us that "The
process of fertilization in sexual generation depends essentially on the
fact that two dissimilar cells meet and blend. In former times the
strangest views prevailed with regard to this act. Men have always been
disposed to regard it as thoroughly mystical, and the most widely
different hypotheses have been framed to account for it. It is only
within a few years that closer study has shown that the whole process of
fertilization is extremely simple, and entirely without special mystery.
Essentially, it consists merely in the fact that the male sperm-cell
coalesces with the female egg-cell. Owing to its sinuous movements, the
very mobile sperm-cell finds its way to the female egg-cell, penetrates
the membrane of the latter by a perforating motion, and coalesces with
its cell material.
"A poet might find in this circumstance a capital opportunity for
painting in glowing colors the wonderful mystery of fertilization; he
might describe the struggles of the 'seed animalcules' eagerly dancing
round the egg-cell shut up in its many coverings, disputing the passage
through the minute pore-canals of the chorion, and then of purpose
burying themselves in the protoplasm of the yelk mass, where, in a
spirit of self-sacrifice, they completely efface themselves in the
better 'ego.' But the critical naturalist very prosaically conceives
this poetical incident, this 'crown of love,' as the mere coalescence of
two cells! The result of this is, that in the first place the egg-cell
is rendered capable of further evolution, and, secondly, that the
hereditary qualities of _both_ parents can be transmitted to the child."
By coalescence is understood, growing together, not mingling as water
and milk might when mixed. More recent observations indicate that during
coalescence both the male and female cells throw off some portions of
their substance. It is also considered that the important part of each
cell is its nucleus. In it all hereditary characteristics are stored up.
If the nucleus be absent in either cell these cells cannot reproduce. In
unicellular, or one-celled, organisms, it has been found in
multiplication by division, a part of the nucleus must go with each
half, otherwise the half without a part of it does not grow. In
experiments in laboratories, artificial division of simple organisms may
be made, and each fragment will become a perfect creature if only a very
small piece of the nucleus goes with the separated portion; but if a
part is cut off without any of the nucleus, then, while it may live on
for a short time, it can not grow or propagate.
Possibly we have here an explanation of some hereditary phenomena in
human beings. If there is an unequal division, and more of the male than
of the female nucleus, the child might, as a result, inherit more of the
father's than of the mother's characteristics, or the reverse.
What has been so far said about the germ plasm has been to enable the
reader to possess a degree of intelligence on the nature of
fertilization, so far as it is known; but from a practical standpoint
the most important knowledge for those prospective parents who wish to
practice intelligent stirpiculture is to understand that the health of
the germ plasm or fertilized ovum depends on the health of the parents.
By health, I mean the possession of a good constitution, to which will
be added a strong hold on life, power to do and to endure, and quickly
to recover from weariness. Disease will be easily warded off in such
persons, so that there will be generally good health. Such a condition
of body is usually inherited. It depends on the possession of a large
supply in the body of living matter--firm muscles, a good heart, lungs
and digestive organs. Those who are feeble cannot endure much; whose
heart, lungs and digestive organs are weak; whose hold on life is
slight, can rarely endow their offspring with these high qualities.
Their children may live if no great strain comes upon them; but if they
must take an active part in the struggle and competition going on in the
world they cannot endure it. Mr. Spencer puts the case very aptly in his
work on Ethics where he says: "It results that where maternal vigor is
great, and the surplus vitality consequently large, a long series of
children may be borne before any deterioration in their quality becomes
marked; while, on the other hand, a mother with but a small surplus may
soon cease altogether to reproduce. Further, it results that variations
in the state of health of parents which involves variations in the
surplus vitality have their effects on the constitutions of offspring to
the extent that offspring borne during greatly deranged maternal health
are decidedly feebler. And then, lastly and chiefly, it results that
after the constitutional vigor has culminated, and there has commenced
that gradual decline which in some twenty years or so brings absolute
infertility, there goes on a gradual decrease in that surplus vitality
on which the production of offspring depends, and a consequent
deterioration in the quality of such offspring. This which is _a
priori_ conclusion is verified _a posteriori_.
"Mr. J. Mathews Duncan, in his work on Fecundity, Fertility, Sterility
and allied topics, has given results of statistics which show that
mothers of twenty-five bear the finest infants, and that from mothers
whose ages at marriage range from twenty to twenty-five years there come
infants which have a lower rate of mortality than those resulting from
marriages consummated when the mothers' ages are smaller or greater. The
apparent slight incongruity between these two statements being due to
the fact that whereas marriages commenced before twenty and twenty-five
cover the whole of the period of highest vigor, marriages commenced at
five and twenty cover a period which lacks the years during which vigor
is rising to its climax and includes only the years of decline from the
climax."
This quotation from Mr. Spencer needs a qualifying remark. Mr. Galton,
in his work on Hereditary Genius, found that the average age of mothers
of men of the greatest ability was about thirty, and of their fathers
thirty-five. In such cases, the physical and intellectual strength must
have been above the average, and, consequently, it continued to a more
advanced age. Besides, those of great ability mature later.
It may also be added that Duncan's statistics, quoted by Spencer, are
average statistics gathered from tables of mortality, and include every
class of persons. Now, average statistics do not apply to individual
cases, and they would not apply to those highly endowed physically and
intellectually.
Further, those who are well endowed at birth and whose lives are in
accordance with hygienic law, that is, those who do not squander their
physiological resources by sensuality, by intemperance, or by excesses
of any sort retain their health to a greater age than those whose lives
are the reverse. Such are of a youthful physiological age, which is not
altogether determined by the actual number of years they have lived, but
by very high physiological conditions.
From all this we conclude that a very important rule in the production
of offspring, if we would have those offspring superior, is to maintain
a high degree of health--a condition in which there is a surplus of
physiological capital to produce children with endowments equal to, if
not superior to, their parents.
Another subject requires treatment here. It is the effect of alcohol on
offspring. We are yet lacking in statistics giving the facts we need to
know on this subject; but the general observation of competent persons
who have had good opportunities to study it may teach us something.
Alcohol, in its circulation in the blood, penetrates every part; not
even the germ plasm escapes. Demme studied ten families of drinkers and
ten families of temperate persons. The direct posterity of the ten
families of drinkers included fifty-seven children. Of these,
twenty-five died in the first weeks and months of their lives; six were
idiots; in five a striking backwardness of their longitudinal growth was
observed; five were affected with epilepsy, and five with inborn
diseases. Thus, of the fifty-seven children of drinkers only ten, or
17.5 per cent., had normal constitutions and healthful growth. The ten
sober families had sixty-one children, five only dying in the first
weeks; four were affected with curable diseases of the nervous system;
two only had inborn defects. The remaining fifty, 81.9 per cent., were
normal in their constitutions and development.
In this statement we have a graphic object lesson of the evil effects of
alcohol on the germ plasm. Natural selection had far more to do in
removing those unfit to survive in the intemperate than in the temperate
families.
A knowledge of the evil effects of alcohol on the unborn child was known
to the ancients. The mother of Sampson was warned "not to drink any wine
or strong drink nor to eat any unclean thing" because she was to
conceive and bear a son who was to deliver Israel out of the hands of
the Philistines. Manoah was so interested in what the angel of the Lord
had said to his wife that he sought an interview with him for further
confirmation, and asked: "How shall we order the child, and how shall we
do unto him?" evidently meaning, "How shall we train and educate him?"
and the same advice was given as before. Whatever view the reader may
hold as to the inspiration or non-inspiration of the Bible, certainly
this advice was good. Other examples similar to it are to be found, not
only in the same book, but in numerous historical works, and also
abundant evidence in our own time of the evil effects of alcoholic
drinks on unborn children giving them a tendency to insanity, idiocy and
other nervous diseases. A whole book might be written on this branch of
our subject.
To what extent food affects the germ plasm we remain somewhat in
ignorance. We know that it is from it that the body is nourished, and
from it also the stored up or surplus matter in our systems is obtained.
The larger the surplus the more highly will the offspring be endowed
with energy is a fact clearly set forth by Mr. Spencer. A surplus of
fatty food stored up in the body, however, cannot be of much service and
may prove injurious. A deficiency of nitrogenous food would also, it
seems to me, be an evil. The germ plasm, or its most important part, is
a highly nitrogenous substance, like all protoplasm, or living matter.
The highest form of germ plasm, that with a most complex molecular
structure, would hardly be formed if there was a deficiency of
nitrogenous matter in the blood.
Air is also food the same as bread is. The activities, the chemical
changes in the body, are mainly, though not entirely, between the oxygen
of the air and the carbon and hydrogen of our food. The body is quite as
much injured by a deficiency of air inhaled into the lungs by exercise
as by a deficiency of food, though the injury may be of a different
nature. Physicians and others have long ago observed that the offspring
of parents living much in the open air and sunlight are healthier and
stronger than those of parents living in confined spaces, where air and
light are deficient. Air which is impure, which is loaded with poisonous
matter, if inhaled for a long time by the mother, lowers the standard of
her health. In malarious regions, the vigor of the offspring is less,
and the number who die in infancy greater, than in regions where the air
and water are pure. Many years ago I remember reading in one of the
journals devoted to sanitary science published in London, an account of
a rural town where both air and water were of extraordinary purity, and
in this town a very large percentage of the children born lived to grow
to maturity. There is also an isolated region in France, bordering on
the sea, where both air, water and climate are unusually salubrious,
and though intermarriage has been practiced for a long time among the
several thousand inhabitants, the people are remarkably well formed and
healthy. Similar facts have been observed in other places. They indicate
to us that a healthful climate, with good air and water, are important
factors in all true stirpiculture.
While all diseases which exhaust the physiological resources of the
system are detrimental to the offspring, there are certain ones which
are peculiarly so. Specific diseases or those resulting from a sensual
life are the first to be mentioned. If the bodies of either father or
mother become saturated with the poison, which is probably a germ, then
the child born of such parents will certainly be infected and either die
at birth or live only a short and feeble life. It is one of the
penalties of an impure life--a very severe one, no doubt, but perhaps
not too severe, that the offspring of the sensualist must suffer the
penalties for its parent's physiological sins. Medical men have long
been trying to discover a remedy which will make it safe for a man
infected with specific disease to marry and become a father, but so far
they have not had much success. It is doubtful if they ever will.
Epilepsy is another disease which is so often transmitted to children
that any one of either sex suffering from it had better abstain from
parentage. If one parent is remarkably healthy, the children may escape
the severest form of penalty; but even then they may suffer from
nervousness and other diseases, and rarely enjoy robust health.
The question whether persons who have a consumptive tendency should
become parents or not has frequently been discussed by sanitarians, but
never settled. Such persons are frequently intellectual, and often of an
unusually cheerful and hopeful disposition. They are, in most cases,
quite prolific. In the female they generally make excellent wives and
mothers; in the case of the male, they are not uncommonly good providers
for their families, and also good fathers. Except in the worst cases,
does the welfare of the race demand that they shall not marry and become
parents. Probably not. But we must advise them to take the very best
care of their imperfect bodies; to develop their chests by wise but not
excessive physical training; to husband their physiological resources
carefully; not to marry young, nor rear too many children. Excessive
childbearing is a prolific cause in women of consumption, and excessive
sexual indulgence is a frequent cause of it in both sexes.
These remarks should not be construed to mean that those who are already
in the early stages of this disease, or whose families on both sides
have been deeply affected by it, may become parents. They should not.
But in the present state of society, we cannot hold men and women up to
an ideal standard. Some slight risks may be taken, but not too great
ones. As the race progresses in knowledge, however, we may raise our
standards, and finally make them so high that no one with a tendency to
any serious disease which is likely to affect the offspring unfavorably
shall have any right to contribute to the world's population.
I have mentioned only a few of the many diseases which affect the germ
plasm unfavorably. It is hardly necessary to extend the list.
One other subject deserves consideration, when I will bring this chapter
to a close. Every child born into the world is, to a certain extent, an
experiment. That is to say, the parents cannot predict its sex, nor what
its chief characteristics will be. These depend on what potentialities
are stored up in the germ plasm. If this be formed by parents in good
health, with a surplus of vital force, and a long line of ancestors with
normal lives, we may believe that if the environment be favorable, the
child will develop so as to show the same characteristics, perhaps in an
even higher degree. Whatever variations there are will not be much below
or above the average line of its ancestors. The congenital characters
will tend to be transmitted. They are in the germ plasm, even in great
detail. Whether the acquired ones are transmitted may still be
uncertain; but whether they are or not, normal right living will be sure
to have good effects. Obey the laws of life and far better results will
follow than if they are disobeyed.
FEWER AND BETTER CHILDREN.
In the present age suggestions on this subject may seem superfluous. The
more highly educated and wealthy classes have already sufficiently
reduced the number of children which they bring into the world. But are
these offspring any better than they would have been had their parents
given birth to a larger number?
Mr. Darwin did not think much could be done to improve the race by
parents limiting the number of their offspring. He would trust to
natural selection to weed out the unfit, and to sexual selection as an
aid. He thus describes the probable manner of action of sexual selection
among primeval men: "The strongest and most vigorous men--those who
could best defend and hunt for their families; those who were provided
with the best weapons and possessed the most property, such as a large
number of dogs or other animals--would succeed in rearing a greater
average number of offspring than the weaker and poorer members of the
same tribes. Such men would doubtless generally be able to select the
more attractive women. . . . If, then, this be admitted, it would be an
unexplainable circumstance if the selection of the more attractive women
by the more powerful men of the tribes, who would rear on the average a
greater number of children, did not, after the lapse of generations,
_modify the character of the tribes_."
The way in which the tribe would be modified would be by its producing
better children. Of course among primitive men the richer and more
powerful had several wives, but it is not likely that the number of
children by each one was large.
Natural selection is, however, a painful process, necessary, no doubt,
where ignorance prevails; but if the number of children of each pair
could be limited and of a superior character, so far as vigor and
adaptation to environment are concerned, would there not be less need
for natural selection with all its evils? It seems to us that this would
be so.
We have already quoted Grant Allen as favoring abstinence from
parenthood on the part of the unfit and the duty on the part of the fit
to become parents, and, theoretically, Mr. Allen is right; but except as
both of these classes are swayed by duty we would make little progress
in this way. A majority of mankind think they are the fit. Why should
they crucify their desires for the benefit of the race? As mankind
becomes more moral Mr. Allen's views may have a larger influence on
thought than now; but before that time little can be expected from
them.