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THE SEXUAL QUESTION
A SCIENTIFIC, PSYCHOLOGICAL, HYGIENIC AND SOCIOLOGICAL STUDY
BY AUGUST FOREL, M.D., PH.D., LL.D. Formerly Professor of Psychiatry at and Director of the Insane Asylum in Zurich (Switzerland)
ENGLISH ADAPTATION FROM THE SECOND GERMAN EDITION, REVISED AND ENLARGED
BY C.F. MARSHALL, M.D., F.R.C.S. Late Assistant Surgeon to the Hospital for Diseases of the Skin, London
BROOKLYN, NEW YORK PHYSICIANS AND SURGEONS BOOK COMPANY HENRY AND PACIFIC STREETS 1931
Copyright, 1906 Copyright, 1922
OWNED BY PHYSICIANS AND SURGEONS BOOK CO.
PRINTED IN U.S.A.
PREFACE TO THE FIRST EDITION
This book is the fruit of long experience and reflection. It has two fundamental ideas—the study of nature, and the study of the psychology of man in health and in disease.
To harmonize the aspirations of human nature and the data of the sociology of the different human races and the different epochs of history, with the results of natural science and the laws of mental and sexual evolution which these have revealed to us, is a task which has become more and more necessary at the present day. It is our duty to our descendants to contribute as far as is in our power to its accomplishment. In recognition of the immense progress of education which we owe to the sweat, the blood, and often to the martyrdom of our predecessors, it behoves us to prepare for our children a life more happy than ours.
I am well aware of the disproportion which exists between the magnitude of my task and the imperfections of my work. I have not been able to study as much as should be done the innumerable works which treat of the same subject. Others, better versed than myself in the literature of the subject, will be able later on to fill this regrettable lacuna. I have endeavored, above all things, to study the question from all points of view, in order to avoid the errors which result from any study which is made from one point of view only. This is a thing which has generally been neglected.
I must express my thanks to my friend, Professor Mahaim, and especially to my publisher and cousin, S. Steinheil, for the help and excellent advice which they have given me in the revision of my work; also to Professor Boveri, who has been kind enough to revise the figures, 1 to 17.
DR. A. FOREL.
Chigny pres Morges (Suisse).
PREFACE TO THE SECOND EDITION
The text of the first edition has been revised and corrected, but, apart from some points of detail, the subject matter has not been changed. The examples at the end of Chapter V (First Edition) no longer form a special appendix; they have been included in the parts of the book which specially concern them; some of them have been omitted as being superfluous.
In the domain with which we are concerned the French public are too much afraid, I think, of crudities and of calling things by their proper name. By veiled words and by indirect locution one may say anything, but I have decided not to employ such subterfuges in treating of such a vital social question with the seriousness that it requires. It seems that there is a fear of young people hearing the sexual question spoken of freely and openly; but it is not taken into account that in hiding these things under half-understood words one only excites their curiosity, and, owing to their being blindfolded, they are delivered into the snares and surprises of debauchery.
I cannot better illustrate the error that I have just pointed out than by quoting, among several others of the same kind, a letter which I have received from a young girl, aged 21 years, intelligent, virtuous, educated, and well brought up, but without restraint.
Having read my book she put several questions to me to which I replied. On my part I requested her to tell me frankly:
(1). If, in her opinion, I had been mistaken in my judgment of the sexual psychology of the normal young girl; (2). If my book had done her the least harm, moral or otherwise.
I begged her to criticise me without pity, for I wished above all things to be clear on the effect produced by my book. This is her letter:
"I must thank you for the deep and unalterable impression which your book has produced on me. I am a young girl of 21 years, and you know how difficult it is for us to see clearly into those natural things which so closely concern us. I cannot, therefore, thank you too much for the calm enlightenment which has been produced in me, and for the just and humane words which you devote to the education of our sex. I hope one day to have the good fortune to apply to my children the ideas on education with which you have inspired me.
"You ask me for the impression which your book has made on me. It is true that I am still very young, but I have read much. My mother has brought me up very freely, so that I can count myself among the young girls who are free from prejudice. In spite of this, a sort of internal anxiety or false shame has hindered me from speaking of all the things of which you treat. All that I knew I had read in books or derived by instinct. Although I knew very well that my mother would always answer my questions I never asked any.
"I declare that latterly my mind had been in a state of veritable chaos. I was obsessed and tormented by a fear of everything of which I was ignorant and some day ought to learn. This is why I was anxious to read your book which a friend showed me. I will now express myself more clearly.
"The first chapters were difficult for me, not because I could not understand them, but owing to the strange and novel experience which the truth made in me when plainly and scientifically expounded. Wishing to read everything I applied myself to the book laboriously. My first impression was that of disgust for all human beings and mistrust of everything. But I was soon glad to find that I was a very normal young girl, so that this impression soon passed away. I was no longer excited over conversations which I heard, but took a real interest in them, and I was happy to have become acquainted with some one who understood us young girls.
"I am, therefore, a young girl whose sensations are neither cold nor perverse, and I am always rejoiced, in reading your book, to see with what truth you describe our sexual impressions. Those who maintain that we feel in this way the same as men make me smile. In your book ("Hygiene of Marriage," p. 479) you say that the idea of marriage awakens in a normal young girl a kind of anguish and disgust, and that this feeling disappears as soon as she has found some one whom she loves. This is extremely true and well observed. I am in complete agreement with a friend with whom I have often discussed your book; we young girls are very little attracted by the purely sexual side of marriage, and we should prefer to see children come into the world by some other way than that ordained by Nature. This will, perhaps, make you laugh. However, I think you will understand my feelings.
"When I had finished reading your book I became absolutely tranquil, and my ideas were enlightened. It goes without saying that it is no longer possible for me to be ingenuous, but I should like to know what one gains by such naivety. It is very easy to be innocent when one knows nothing, and this is of no account. I never thought for a moment to find your book immoral, and that is why I do not think you have done me any harm. Excuse me for having written at such length, but I could not abbreviate when dealing with such a serious question."
The author of this letter has, at my request, authorized me to publish it anonymously. I think that the candor, the loyalty and the maturity of judgment of the sentiments expressed by this young girl are of much more value and are much more healthy than all the prudishness and false shame of our conventional morality.
DR. A. FOREL.
Chigny pres Morges (Suisse).
CHAPTER I PAGE The reproduction of living beings—History of the germ— Cell-division—Parthenogenesis—Conjugation—Mneme—Embryonic development—Difference of sexes—Castration—Hermaphrodism— Heredity—Blastophthoria 6
The evolution or descent of living beings 39
Natural conditions of mechanism of human coitus—Pregnancy— Correlative sexual characters 49
The sexual appetite in man and woman—Flirtation 72
Love and other irradiations of the sexual appetite in the human mind—Psychic irradiations of love in man: Procreative instinct, jealousy, sexual braggardism, pornographic spirit, sexual hypocrisy, prudery and modesty, old bachelors—Psychic irradiations of love in woman: Old maids, passiveness and desire, abandon and exaltation, desire for domination, petticoat government, desire of maternity and maternal love, routine and infatuation, jealousy, dissimulation, coquetry, prudery and modesty—Fetichism and anti-fetichism— Psychological relations of love to religion 104
Ethnology and history of the sexual life of man and of marriage—Origin of marriage—Antiquity of matrimonial institutions—Criticism of the doctrine of promiscuity— Marriage and celibacy—Sexual advances and demands of marriage—Methods of attraction—Liberty of choice—Sexual selection—Law of resemblance—Hybrids—Prohibition of consanguineous marriages—Role of sentiment and calculation in sexual selection—Marriage by purchase—Decadence of marriage by purchase—Dowry—Nuptial ceremonies—Forms of marriage—Duration of marriage—History of extra-nuptial sexual intercourse 144
Sexual evolution—Phylogeny and ontogeny of sexual life 192
Sexual pathology—Pathology of the sexual organs—Venereal disease—Sexual psychology—Reflex anomalies—Psychic impotence—Sexual paradoxy—Sexual anaesthesia—Sexual hyperaesthesia—Masturbation and onanism—Perversions of the sexual appetite: Sadism, masochism, fetichism, exhibitionism, homosexual love, sexual inversion, pederosis, sodomy—Sexual anomalies in the insane and psychopathic— Effects of alcohol on the sexual appetite—Sexual anomalies by suggestion and auto-suggestion—Sexual perversions due to habit 208
The role of suggestion in sexual life—Amorous intoxication 277
The relations of the sexual question to money and property— Prostitution, proxenetism and venal concubinage 293
The influence of environment on sexual life—Influence of climate—Town and country life—Vagabondage—Americanism— Saloons and alcohol—Riches and poverty—Rank and social position—Individual life—Boarding schools. 326
Religion and sexual life 340
Rights in sexual life—Civil law—Penal law—A medico-legal case 358
Medicine and sexual life—Prostitution—Sexual hygiene— Extra-nuptial intercourse—Medical advice—Means of regulating or preventing conception—Hygiene of marriage— Hygiene of pregnancy—Medical advice as to marriage—Medical secrecy—Artificial abortion—Treatment of sexual disorders 418
Sexual morality 445
The sexual question in politics and in political economy 461
The sexual question in pedagogy 470
The sexual question in art 489
Conclusions—Utopian ideas on the ideal marriage of the future—Bibliographical remarks 499
THE SEXUAL QUESTION
THE SEXUAL QUESTION
My object is to study the sexual question under all its aspects: scientific, ethnological, pathological and social, and to seek the best solution of the numerous problems connected with it. Unfortunately, in publications dealing with this subject, eroticism usually plays a considerable part, and it is difficult for an author to abstract himself from this, for it is reflected unconsciously in his thoughts. As all sentiment, more or less, warps judgment, it is the duty of scientific criticism to eliminate eroticism in order to be exact and impartial. We shall, therefore, do all that is possible to free ourselves from it in the course of the present study.
The sexual question is of fundamental importance for humanity, whose happiness and well-being depend largely on the best solution of this important problem. In dealing with such a delicate subject I shall endeavor to avoid narrow-mindedness and prejudice; I shall avoid tiresome quotations, and shall only employ technical terms when necessary, as they rather interfere with the comprehension of the subject. I shall take care to explain all those which appear to me indispensable.
My opinions on the sexual question are based, on the one hand, on my scientific study of the human brain, and on the other hand on the long personal experience of an alienist who has devoted himself almost as much to normal mentality and questions of social hygiene as to pathological mentality. I have, however, been obliged to rely on the fundamental work of Westermark with regard to ethnology, this subject being strange to me. Concerning sexual psycho-pathology I have followed the classification of Krafft-Ebing.
The sexual question is extraordinarily complex, and we cannot expect to find a simple solution for it as we can for the questions of alcoholism, slavery, torture, etc. The latter are solved in one word—suppression. Suppression of slavery and torture; suppression of the usage of alcoholic drinks. We are concerned here with ulcers artificially produced and preserved in human society; ulcers which must be simply extirpated. Their suppression is nothing but beneficial, since, far from being connected with the normal conditions of human existence, they place it in peril. Sexual instinct and sentiment, on the contrary, have their roots in life itself; they are intimately bound up with humanity, and therefore require quite a different treatment. But human society has guided them into false and pernicious ways. It is important to turn them from these in order to tranquilize and regulate their course by damming them up and canalizing them.
The fundamental axiom of the sexual question is as follows:
With man, as with all living beings, the constant object of all sexual function, and consequently of sexual love, is the reproduction of the species. It is therefore necessary to treat the question from the point of view of the natural sciences, physiology, psychology and sociology. This has already been done more than once, but usually in erudite treatises which only look upon one side of the question; or, on the other hand, in a superficial and often frivolous manner.
To ensure happiness, humanity should desire to reproduce itself in a manner which elevates progressively all the physical and mental faculties of man, with regard to health and bodily strength, as much as to sentiment, intelligence, will, creative imagination, love of work, joy of living, and the sentiment of social solidarity. Every attempt made to solve the sexual question should, therefore, be directed toward the future and toward the happiness of our descendants.
It requires much disinterestedness to attempt seriously any sexual reform. But, as the human subject is by nature extremely weak, as his views are limited, especially in the matter which concerns us, it is absolutely necessary, if we would avoid Utopia, to adapt the fundamental aim of sexual union to happiness and joy, even to the natural weakness of man.
The fundamental difficulty of the problem lies in the necessity for such an adaptation, and this difficulty requires us to make a clean sweep of prejudices, traditions and prudery. It is this which we wish to attempt.
Considered from an exalted point of view, sexual life is beautiful as well as good. What there is in it which is shameful and infamous is the obscenity and ignominy caused by the coarse passions of egoism and folly, allied with ignorance, erotic curiosity and mystic superstition, often combined with social narcotic intoxication and cerebral anomalies.
We shall divide our subject into nineteen chapters. Chapters I to VII deal with the natural history and psychology of sexual life; Chapter VIII with its pathology, and Chapters IX to XVIII with its social role, that is to say, its connection with the different domains of human social life.
THE REPRODUCTION OF LIVING BEINGS
History of the Germ:—Cell-division—Parthenogenesis— Conjugation—Mneme—Embryological Development—Difference of the Sexes—Castration—Hermaphrodism—Heredity—Blastophthoria.
A general law of organic life decrees that every living individual is gradually transformed in the course of a cycle which is called individual life, and which terminates with death, that is by the destruction of the greater part of the organism. It then becomes inert matter, and the germinative cells alone of all its parts continue its life under certain conditions.
The Cells: Protoplasm. The Nucleus.—Since the time of Schwann (1830) it is agreed that the cell is the most simple morphological element which is capable of living. Among the lower organisms this element constitutes the entire individual. There is no doubt that the cell is already a thing of high organization. It is formed of infinitely small elements of very different value and chemical constitution, which form what is called protoplasm or the cell-substance. But these infinitely small elements are so far absolutely unknown. It is in them that must be sought the change from inanimate matter, that is the chemical molecule, to living matter, a change which was formerly believed to lie in the protoplasm itself, before its complicated structure was known. We need not concern ourselves here with this question which remains an open one.
Life being established, the cell remains its only known constant element. The cell is composed of protoplasm which contains a rounded nucleus formed of nucleo-plasma. The nucleus is the most important part of the cell, and governs its life.
Cell-division.—The lowest unicellular organisms, as each cell of a multicellular organism, reproduce themselves by division or fission. Each cell originates from another cell in the following manner: the cell divides in the center as well as its nucleus, and in this way forms two cells which grow by absorbing by endosmosis (filtration) the nutritive juices which surround them. Death or destruction of the cell is therefore death of the entire organism when this is unicellular. But it has been previously reproduced.
We find here already the special and fundamental act of conjugation, that is the fusion of two cells into one, which serves to strengthen reproduction. This act, common to all living things including man, shows us that continuation of life is only possible when from time to time different elements, that is elements which have been exposed to different influences, combine together. If this conjugation is prevented and life is allowed to continue indefinitely by means of fission or by budding (vide infra), there results a progressive weakening and degeneration which leads to the disappearance of the whole group thus reproduced.
It is necessary to explain here the results of recent scientific work on the intimate phenomena of cell-division, for they are closely allied to those of fecundation.
The nucleus of an ordinary cell presents itself in the form of a nearly spherical vesicle. Delicate methods of staining have shown that the nucleus encloses several round nucleolar corpuscles, and also a reticulum which is attached to its membrane and spreads through its whole substance. The liquid part of the nucleus fills the meshes of this reticular tissue, which stains easily and for this reason is named chromatin. The phenomena of cell division in well-developed cells with nuclei is termed mitosis. Certain lower forms of cells exist in which the nucleus is not well differentiated. Mitosis begins in the nucleus (Plate I). Figure 1 represents the cell before division has commenced. In the protoplasm, by the side of the nucleus, is formed a small corpuscle (c) which is called the centrosome. The nucleus itself is marked b. When the cell commences to divide, the meshes of the network of chromatin contract and the centrosome divides into two parts (Fig. 2). Shortly afterward the particles of chromatin concentrate in the form of convoluted rods called chromosomes (Figs. 3 and 4). The number of these varies according to the species of organism, but remains constant for each animal or vegetable species. At the same time the two centrosomes separate from each other on each side of the nucleus. The chromosomes then become shorter and thicker while the nucleus is completely dissolved in the protoplasm of the cell, and its membrane disappears (Fig. 4).
Directly afterwards the chromosomes arrange themselves regularly in line, like soldiers at drill, following one of the larger diameters of the cell, and forming a barrier between the two centrosomes (Fig. 5). Each of the chromosomes then divides into two parallel halves of equal thickness (Fig. 6).
Figures 3 and 4 show that, while these changes are being produced, each of the two centrosomes is surrounded by stellate rays. Some of these rays extending in the direction of the chromosomes, become attached to one of their extremities and draw it toward the corresponding centrosome (Fig. 7). Thus around each centrosome are grouped as many chromosomes as the mother cell possessed itself (Fig. 8). Simultaneously, the cell enlarges and its protoplasm commences to become indented at each end of the diameter previously formed by the chromosomes. From this moment the nuclear liquid concentrates itself around each of the groups of chromosomes, the rays disappear and the cell divides into two halves, each containing a group of chromosomes (Fig. 9); the indentation increases so as to form a partition across the protoplasm. The chromosomes then form a new meshwork of nuclear chromatin, and we have then two cells each with a nucleus and a centrosome like the mother cell (Fig. 10).
This is what takes place in the reproduction of all cells of the animal and vegetable kingdoms. In the simplest unicellular organisms which are known fission constitutes the only means of reproduction. In the complicated organisms of the higher plants and animals each cell divides in the manner indicated above, both in the embryonic period and later on during the development of each of the organs which forms the organism. This fact shows more than any other the intimate relationship which connects all living organisms. The most remarkable thing, perhaps, is the almost mathematical division of the chromosomes into two halves, a division which results in the equal distribution of their substance through the whole organism. We shall return to this point later on.
Reproduction by Budding. Parthenogenesis. In the animal and vegetable kingdoms the higher organisms become more and more complicated. They are no longer composed of a single cell, but of an increasing number of these cells combined in a whole, of which each part, adapted for a special purpose, is itself formed of cells, differentiated as much by their organic form as by their chemical and physical constitution. In this way, in plants, are formed the leaves, flowers, buds, branches, trunk, bark, etc.; and in animals the skin, intestine, glands, blood, muscles, nerves, brain, sense organs, etc. In spite of the great complication of the divers living multicellular organisms, one often finds among them the power of reproduction by fission or by budding. In certain animals and plants, groups of cells vegetate in buds which separate from the body later on and form a new individual; this occurs among the polypi and plants with bulbs, etc. One can even form a tree by means of a cutting. Ants and bees, which have not been fecundated, are capable of laying eggs which develop by parthenogenesis (virgin parturition) and become complete individuals. But these degenerate and disappear if reproduction by parthenogenesis or budding is continued during several generations.
Among the higher animals, the vertebrates and man, there is no reproduction without conjugation; no parthenogenesis or budding. So far as we have studied the question we see in the animal and vegetable kingdoms sexual reproduction, or conjugation, as a sine qua non for the indefinite continuation of life.
The Sexual Glands. The Embryo. However complicated the organism, it always possesses a special organ, the cells of which, all of the same form, are reserved for the reproduction of the species and especially for conjugation. The cells of these organs, called sexual glands, have the power of reproducing themselves so that they reconstruct the whole individual (the type of the species) from which they arose, in an almost identical form, by conjugation (sometimes also, for a certain time, by parthenogenesis) under certain fixed conditions as soon as they leave its body. We can thus say with Weismann, speaking philosophically, that these germinal cells continue the life of their parents, so that in reality death only destroys part of the individual, namely, that which has been specially adapted for certain exclusively individual ends. Each individual, therefore, continues to live in his descendants.
The germinal cell divides into a number of cells called embryonic, which become differentiated into layers or groups which later on form the different organs of the body. The embryonic period is the name given to the period between the exit of the germinal cell from the maternal body and the final complete development which it acquires in becoming the adult individual. During this period the organism undergoes the most singular metamorphoses. In certain cases it forms a free embryo which appears to be complete, having a special form and mode of life, but which finally becomes transformed into an entirely different sexual individual. Thus from the egg of a butterfly there first emerges a caterpillar, which lives and grows for some time, then changes to a chrysalis and finally to a butterfly. The caterpillar and the chrysalis belong to the embryonic period. During this period every animal reproduces in an abbreviated manner certain forms which resemble more or less those through which its ancestors have passed. The caterpillar, for example, resembles the worm which is the ancestor of the insects. Haeckel calls this the fundamental biogenetic law. We are not concerned here with embryology, and will content ourselves with some of the main points.
Germinal Cells. Hermaphrodites. We now come to conjugation. In order to avoid complications we will leave aside plants and speak only of animals. Among multicellular animals, sometimes in the same individual, sometimes in different individuals, occur two kinds of sexual glands, each containing one kind of cells—the male cells and the female cells. When both kinds of sexual glands occur in the same individual, the animal is said to be hermaphrodite. When they develop in two different individuals the animals are of distinct sexes. Snails, for example, are hermaphrodite. There also exist lower multicellular animals which reproduce by budding, but among which conjugation takes place from time to time. We shall not consider these animals any further, as they are too remote to interest us here.
Spermatozoa and Ova.—In all the higher animals, including the hermaphrodites, the male germinal cells, or spermatozoa are characterized by their mobility. Their protoplasm is contractile and their form varies according to the species. In man and vertebrate animals they resemble infinitely small tadpoles, and their tails are equally mobile. The female germinative cell, on the contrary, is immobile and much larger than the male cell. Conjugation consists in the movement of the male cell, by means of variable mechanism, toward the female cell, or egg, into the protoplasm of which it enters. At this moment it produces on the surface of the egg a coagulation, which prevents the entrance of a second spermatozoid.
The egg and the spermatozoid both consist of protoplasm containing a nucleus. But, while the spermatozoid has only a small nucleus and very little protoplasm, the egg has a large nucleus and a large quantity of protoplasm. In certain species the protoplasm of the egg grows in the maternal organism in a regular manner to form the vitellus (yolk of egg) which serves as nourishment for the embryo for a long period of its existence. This occurs in birds and reptiles.
Conjugation.—The phenomena of conjugation were made clear by van Beneden and Hertwig. These phenomena, as we have seen, commence among unicellular organisms. In these they do not constitute reproduction, but the vital reenforcement of certain individuals. Conjugation takes place in a different manner in different cases.
For example, a unicellular animal applies itself against one of its fellows. The nucleus of each cell divides into two. Then the protoplasm of the two cells fuses over the whole surface of contact, and half the nucleus of the first cell penetrates the second cell, while half the nucleus of the latter enters the first cell. After this exchange the cells separate from each other and each exchanged half of the nucleus fuses with the primitive half of the nucleus remaining in the cell.
From this moment each cell continues to reproduce itself by fission, as we have seen above. In another form, two cells meet and fuse completely. Their nuclei become applied against each other and each exchanges half its substance with the other as in the preceding case, so that the final result is the same. In both cases the two conjugated cells are identical, and one cannot call them male and female.
Penetration of the Spermatozoid into the Egg.—In all the higher animals in which the germinal cells are of two kinds, male and female, conjugation takes place in rather a different manner. Here, the female cell or egg only reproduces itself exceptionally by parthenogenesis. It usually contains no chromosomes and often too little chromatin, so that it perishes when conjugation does not occur.
The spermatozoid swims by means of its tail to meet the egg. As soon as it touches it it penetrates it and the coagulation which we have mentioned is produced. This coagulation forms the vitelline membrane, which prevents the entry of other spermatozoids. If, from pathological causes the entry of several spermatozoids takes place, there results, according to Fol, a double or triple monster.
In Fig. 11 on Plate II, we see the egg with its vitelline membrane and nucleus, the chromatin network of which is marked in blue: b shows the protoplasm of the egg or vitellus; a the vitelline membrane; d the spermatozoid which has just entered, and the nucleus of which, composed chiefly of chromatin, is colored red, while its tail has performed its task and is about to disappear. The letters e, f, and g, show a spermatozoid which has arrived too late.
Before the head of the spermatozoid which has entered, appears a centrosome (Fig. 12) which it brings to the egg with its small amount of protoplasm, and around this centrosome rays form, as in the case of cellular fission. At the same time a nuclear liquid arising from the protoplasm of the egg becomes concentrated around the chromatin of the spermatozoid, while the nucleus of the egg remains in place and does not change. The nucleus of the spermatozoid, on the contrary, begins to grow rapidly. It forms half the number of chromosomes corresponding to the cell of the species to which it belongs, and grows at the expense of the vitellus of the egg. During this time the centrosome divides into two halves, which progress slowly on each side toward the periphery of the egg, as in the case of fission (see Plate I), while the chromatin of the chromosomes of the spermatozoid is dissolved in the network. The nucleus thus formed by the spermatozoid enlarges more and more (Figs. 13 and 14) till it attains the size and shape of that of the egg (Fig. 15). The male and female chromatin are colored red and blue respectively.
Then only commences activity of the nucleus of the egg, at the same time as fresh activity on the part of the nucleus of the spermatozoid. Before this, however, the nucleus of the egg has thrown off a part of its chromatin called a polar body, and it now possesses only half as much chromatin as the other cells of the body of the individual. The nucleus of the egg and that of the spermatozoid then begin at the same time to concentrate their chromatin in the form of chromosomes (Fig. 16) which arrange themselves regularly in the middle line exactly as shown in Plate I, and divide longitudinally into two halves which are then attracted in opposite directions by the rays of each of the centrosomes (Fig. 17). Figure 17, of Plate II, thus corresponds exactly to Fig. 6, of Plate I.
In fact, the growth of the nucleus of the spermatozoid has given to its substance the same power of development as to that of the nucleus of the egg. Both enter into conjugation in equal parts, which symbolizes the social equality and the rights of the two sexes!
The signification of these facts is as follows: as soon as, in the course of development, the conjugated nuclei divide again into two cells, as in Figs. 7 to 10, of Plate I, each of these two cells contains almost the same quantity of paternal as maternal chromatin. We do not say exactly as much, for the paternal and maternal influences are not divided equally in the descendants. This phenomenon may be explained by what Semon calls alternating ecphoria in mnemic dichotomy. (Vide infra.) As cell division continues in the same way during embryonic life, it follows that each cell, or at least each nucleus of the future organism, will contain on the average half its substance and energy from the paternal and half from the maternal side.
Heredity. The Mneme.—The secret of heredity lies in the phenomena which have been just described. Hereditary influence preserves all its primary power and original qualities in the chromosomes, which enlarge and divide, while the vitelline substance, absorbed by the chromosomes and transformed by the vital chemical processes into the specific substance of the chromosomes, loses its specific and plastic vital energy, as completely as the food which we swallow loses its energy in forming the structure of our living organs. We do not acquire any of the characters of the ox by eating beefsteaks; and the spermatozoid, after eating much vitelline protoplasm, preserves its own hereditary energies, increased and fortified, but without change in their qualities.
In this way the nuclear chromatin of our germinal cells becomes the carrier of all the hereditary qualities of the species (hereditary mneme), and more especially those of our direct ancestors. The uniformity of the intracellular phenomena in cell division and conjugation proves, however, that, without being capable of reproducing the individual, the other non-germinal cells of the body may also possess these hereditary energies, and that there exists, hidden behind all these facts, an unknown law of life, the explanation of which is reserved for the future.
However, a recent work based on an idea of the physiologist, E. Hering, which looks upon instinct as a kind of memory of the species, opens up a new horizon. I refer to the book of Richard Semon: "The mneme considered as the conservative principle in the transmutations of organic life." (Die Mneme als erhaltendes Prinzip im Wechsel des organischen Geschehens, Leipzig, 1904.)
Conception of Irritation.—By the aid of the fundamental facts of morphological science, biological and psychological, Semon proves that Hering's idea is more than an analogy, and that there is a fundamental identity in the mechanism of organic life. In order to avoid the terminology of psychology which tends to be equivocal, Semon employs some new terms to designate his new ideas, based on the fundamental conception of irritation in its physiological sense.
Semon defines irritation as an energetic action on the organism which determines a series of complicated changes in the irritable substance of the living organism. The condition of the organism thus modified, which lasts as long as the irritation, is called by Semon the state of irritation. Before the action of irritation, the organism is in a condition which Semon calls the primary state of indifference, and after its action, in the secondary state of indifference.
Engram. Ecphoria.—If, when an irritation has entirely ceased, the irritable substance of the living organism becomes modified permanently during its secondary state of indifference, Semon calls the action engraphic. To the modification itself he gives the word engram. The sum of the hereditary and individual engrams thus produced in a living organism is designated by the term mneme. Semon gives the name ecphoria to the revival of the engram by the repetition of part only of the original irritation, or by the entire but weakened reproduction of the whole state of irritation of the organism, which was originally produced in a synchronous manner with the primary irritation.
Thus, an engram may be ecphoriated (that is to say, reproduced or revived) by the return of one part of the complex of primary irritations which produced it. A young dog, for example, is attacked by urchins who throw stones at it. It experiences two kinds of irritation: (1) the urchins stooping down and throwing stones (optic irritation); (2) the pain caused by the stones (tactile irritation).
In its brain are produced two associated series of corresponding engrams. Previously, this dog did not react when it saw people stoop down. From this moment it will run away and howl at the sight, without any stone being thrown at it. Thus the tactile engram will be ecphoriated by the repetition of the original associated irritation. In the same way, the image of a tree in a known landscape will ecphoriate the entire landscape.
Moreover, an engram may be revived by the enfeebled return of the primary irritating agent which produced it, or by an analogous enfeebled irritation. Thus, the sight of a photograph will revive the image of a known person. A certain kind of maize imported for a long time into Norway and influenced in that country during many generations by the sun of the long summer days, finally accelerated its time of maturation. When imported again to the south of Europe it first preserved its faculty of accelerated maturation in spite of the shortness of the days (Schuebeler). Semon gives a series of analogous examples which show how engrams repeated during several generations accumulate and end by becoming ecphoriated when they have acquired enough power.
Engrams may be associated simultaneously in space, such as those of sight. But they may also be associated in succession, such as those of hearing and of ontogeny. Simultaneous engrams are associated in every direction with the same intensity. Successive engrams, on the contrary, are associated more strongly forwards than backwards, and have only two poles. In the succession a b, a acts more strongly on b than b on a. In the successions of engrams it often happens that two or more analogous engrams are associated in a manner more or less equivalent to a preceding engram. Semon calls this phenomenon dichotomy, trichotomy, etc. But in the successions, two engrams cannot be ecphoriated simultaneously. Hence the phenomenon which Semon names alternating ecphoria; that is sometimes one, sometimes the other of the constituent engrams, for example, of a dichotomy, which arrives at ecphoria. Similarly, the engram of the ecphoriated dichotomy is most often that which has been previously most often repeated.
In the laws of ontogeny and heredity alternating ecphoria plays an important part. The branch less often repeated remains latent and the other only is ecphoriated. But certain combinations which reenforce the latent branch or paralyze the other may induce ecphoria of the first to the second generation.
Semon also shows that the phenomena of regeneration in the embryo, as well as those of the adult, obey the law of the mneme.
Homophony.—The terms engram and ecphoria correspond to the well-known introspective phenomena in psychology of memory and the association of ideas. Engrams are thus ecphoriated. At the time of such phenomena every mnemic irritation of the engrams vibrates simultaneously with the state of synchronous irritation produced by a new irritation. This simultaneous irritation is named by Semon homophony. When a partial discord is produced between the new irritation and the mnemic irritation, the organism always tends to reestablish homophony (harmony). This is seen in psychological introspection by activity of attention; in embryology by the phenomenon of regeneration; and in phylogeny by that of adaptation.
Relying on these convincing facts, Semon shows that irritative actions are only localized at first in their zone of entry (primary zone); but that afterward they irradiate or vibrate, gradually becoming weaker in the whole organism (not only in the nervous system, for they also act on plants). By this means, engraphia, although infinitely enfeebled, may finally reach the germinal cells. Semon then shows how the most feeble engraphias may gradually arrive at ecphoria, as the result of numerous repetitions (in phylogeny after innumerable generations). This is how the mnemic principle allows us to conceive the possibility of an infinitely slow heredity of characters acquired by individuals, a heredity resulting from prolonged repetition.
The facts invoked by Weismann against the heredity of acquired characters lose nothing of their weight by this, for the influence of crossing (conjugation) and selection transforms the material organic forms in an infinitely more rapid and intense manner than individual mnemic engraphias. The latter, on the other hand, furnish the explanation of the mutations of de Vries, which appear to be only sudden ecphoria of accumulated long engraphic actions.
The way in which Semon studies and discusses the laws of the mneme in morphology, physiology and psychology, is truly magisterial, and the perspective which opens out from these new ideas is extensive. The mneme, with the aid of the energetic action of the external world, acts on organisms by preserving them and combining them by engraphia, while selection eliminates all that is ill-adapted, and homophony reestablishes the equilibrium. The irritations of the external world, therefore, furnish the material for the construction of organisms. I confess to having been converted by Semon to this way of conceiving the heredity of acquired characters. Instead of several nebulous hypotheses, we have only one—the nature of mnemic engraphia. It is for the future to discover its origin in physical and chemical laws.
I must refer my readers to Semon's book, for this volume of 343 pages, filled with facts and proofs, cannot be condensed into a few paragraphs.
Each Cell bears in itself Ancestral Energy. As we have already seen, the germinal, cells are not the only ones which possess the energies of all the characters of the species. On the contrary it becomes more and more certain, from further investigation, that each cell of the body bears in itself, so to speak, all the energies of the species, as is distinctly seen in plants. But in all the cells which are not capable of germinating, these energies remain incapable of development. It results that such energies, remaining virtual, have no practical importance.
In an analogous sense we may say that all the cells of the body are hermaphrodite, as all germinal cells, for each possesses in itself the undifferentiated energies of each sex. Each spermatozoid contains all the energies of the paternal and maternal ancestry of man, and each egg those of the paternal and maternal ancestry of woman. The male and the female are only the bearers of each kind of germinal cells necessary for conjugation, and each of these bearers only differs from the others by its sexual cells and by what is called correlative sexual differences. But we must not forget that the germinal cells themselves are only differentiated at a certain period in the development of the embryo; they are thus hermaphrodite originally and only become male and female later.
New experiments made on the eggs of sea urchins and other organisms have shown that conjugation may be replaced by an external irritating agent; for example, the action of certain chemical substances is sufficient to make eggs develop by parthenogenesis which would have died without this action. An entire being has been successfully produced from an egg divided into two by means of a hair. And even from the protoplasm of the egg without its nucleus, with the aid of a spermatozoid. We must not, however, base premature hypotheses on these facts.
When a female cell, or egg, develops without fecundation (parthenogenesis) its nucleus enlarges and divides in the same manner as conjugated nuclei (mitosis).
A point of general interest is what is called the specific polyembryony of certain parasitic insects (hymenoptera of the genus Encyrtus). According to Marchal, their eggs grow and divide into a considerable number of secondary eggs, each of which gives rise to an embryo and later on a perfect insect. By shaking the eggs of certain marine animals they have been caused to divide into several eggs and thus to produce several embryos. All the individuals arising from the division of the same egg of Encyrtus are of the same sex.
Embryology.—It is not necessary to describe here in detail the different changes which the two conjugated cells pass through to become an adult man. This is the object of the science of embryology. We shall return to this in Chapter III. A few words are necessary, however, to explain the general principles.
Ovulation. The corpus luteum.—The ovaries of woman (Fig. 18) contain a considerable number of cells or ovules, although infinitely less than the number of spermatozoids contained in the testicles. From time to time some of these ovules enlarge and are surrounded by a vesicle with liquid contents, which is called the Graafian follicle. At the time of the monthly periods an egg (sometimes two) is discharged from its Graafian follicle, from one or other ovary. This phenomenon is called ovulation. The empty follicle becomes cicatrized in the ovary and is called the corpus luteum (yellow body).
The egg after its discharge arrives at the abdominal orifice of the Fallopian tube, which communicates directly with the abdominal cavity. Some authors state that the end of the tube becomes applied against the ovary by the aid of muscular movement and, so to speak, sucks in the discharged ovule, while others hold that the movements of the vibratile cilia, with which the epithelium of the tubes is furnished, suffice to draw the ovule into its cavity. Figure 18 explains this phenomenon.
Having arrived in the tube, the ovule moves very slowly in the almost capillary tube by means of the vibratile cilia and arrives in the cavity of the womb. Fecundation probably takes place most often at the entrance to the tube or in its canal; sometimes possibly in the womb. On some occasions a squad of spermatozoids advances to meet the descending egg, and numerous spermatozoids are often found in the tubes, even as far as the abdominal cavity.
Fixation of the egg. Formation of the Decidua.—After fecundation, the egg becomes attached to the mucous membrane of the cavity of the womb. This mucous membrane proliferates and becomes gradually detached from the womb to form the membrana decidua which envelops the egg or ovule. An egg fecundated and fixed in this way may keep its position and grow during the first weeks of pregnancy, by the aid of villosities covering its envelope which penetrate the wall of the womb.
[Illustration: FIG. 18. Diagrammatic section in median plane of the female genital organs. It shows the position of an ovule which has just been discharged lying in the opening of the right tube, and that of another ovary fecundated and surrounded by the decidual membrane. In reality this could hardly coexist with the other ovule freely discharged. In the right ovary are seen ovules in various degrees of maturity in their Graafian follicles: also a corpus luteum—an empty Graafian follicle after expulsion of the ovule. The figure also shows the end of the penis in the vagina at the moment of ejaculation of semen, and the position of a preventive to avoid fecundation.]
The womb. The placenta. The womb or uterus is the size of a small egg flattened in one direction. It terminates below in the neck or cervix, which is prolonged into the vagina as a projection, called the vaginal portion of the uterus. The cavity of the womb is continued into the neck and opens below in the vagina by an aperture which is round in virgins and is called the external os uteri. The walls of the womb consist of a thick layer of unstriped muscle. When childbirth takes place it causes tearing which makes the external os uteri irregular and fissured. During copulation the aperture of the penis or male organ is placed nearly opposite the os uteri, which facilitates the entrance of spermatozoa into the uterus. (For the illustration of these points see Fig. 18.)
The vitellus and the membrane of the egg enlarge with the embryo and absorb by endosmosis the nutritive matter necessary for the latter, contained in the maternal blood. The womb itself enlarges at the same time as the embryo.
The fasciculus attached to the embryo is the allantois which becomes the umbilical cord. The vertebrae are already easy to recognize in this embryo. The embryo is formed from a portion of blastoderm, that is to say, from the cellular layer applied to the membranes of the egg and arising from the successive divisions of the two primary conjugated cells and their daughter cells. The embryo has the form of a spatula with the head at one end and the tail at the other. From its walls is detached a surrounding vesicle (Fig. 20) called the amnion, while another vesicle, the umbilical vesicle, grows from its ventral surface and serves, in birds, for the vitelline circulation of the egg which is detached from the mother's body.
In man, the umbilical vesicle is unimportant. In its place the circulation of the blood takes place by the aid of another vesicle, called the allantois, which arises from the intestine of the embryo, and which becomes attached to the walls of the womb in the form of a thick disk called the placenta.
The placenta is formed of dilated blood vessels which meet the maternal blood vessels, also dilated, in the uterine wall, allantois later on becomes the umbilical cord.
In the placenta the embryonic and maternal vessels without actually communicating, are placed in intimate contact, which allows nutritive matter and oxygen to pass by endosmosis from the maternal vessels to those of the embryo. Figure 21 shows a human embryo at the beginning of the fifth week of pregnancy.
Duration of pregnancy. Birth. Pregnancy lasts from conjugation, which is synonymous with conception, till birth, that is about nine months (ten lunar months of four weeks). The embryo is then ready to separate from the maternal body (Fig. 22). By the act of birth it is expelled violently, bringing with it the umbilical cord and the placenta (Fig. 23). Immediately afterward the empty womb contracts strongly and gradually recovers its former size. The sudden interruption of its communications with the maternal circulation deprives the embryo, which has suddenly become a child, of its nutritive matter and oxygen.
In order to avoid suffocation it is obliged to breathe atmospheric air immediately, for its blood becomes dark by saturation with carbonic acid, which irritates the respiratory nerve centers. The first independent act of the new-born child is, therefore, a nervous reflex determined by asphyxia, and is performed with the first cry. Soon afterward the infant begins to suck, so as not to die of hunger, while the umbilical cord, having become useless, shrivels up, and the placenta is destroyed (some animals eat it). The new-born infant is only distinguished from the embryo soon after birth by its breathing and crying.
We may, therefore, say that infancy, especially early infancy, is only a continuation of embryonic life. The transformations which the infant undergoes from birth to adult age are known to all. They take place more and more slowly, except at the relatively short period of puberty.
Formation of the sexual glands.—We must remember that at a very early embryonic period certain groups of cells are reserved to form later on the sexual glands. These cells are at first neither male nor female, but are undifferentiated; later on they become differentiated to form in certain individuals, called males, the testicles with their spermatozoa, and in others, called females, the ovaries with their eggs. On this differentiation depends the sex of the individual, and, according as it takes place in one way or the other, all the rest of the body develops with the correlative sexual characters of the corresponding sex (at first the external genital organs peculiar to each sex, then the beard in man, the breasts in woman, etc).
Castration. Correlative sexual characters.—Castration is the term applied to the extirpation of the sexual glands. When it takes place in infancy it causes a considerable change in the whole subsequent development of the body, especially in man, but also in woman. Man becomes more slender, preserves a high and infantile voice, and his sexual correlative characters develop incompletely or not at all. Eunuchs are men castrated, usually in infancy. To ensure more safety in their harems the Orientals not only remove the testicles but also the penis. Bullocks and horses are bulls and stallions castrated at an early age, and can be distinguished at first sight from normal males. Females who have undergone castration become fat and sometimes take on certain masculine characters. Male human eunuchs have a high-pitched voice, a narrow chest; they remain beardless or nearly so, and have an effeminate character, often intriguing. In both sexes there is a tendency to neurosis and degeneration. It is a mistake to qualify the peculiarities of the male eunuch in the terms of female peculiarities; there is only a relative tendency. The eunuch is no more a woman than a bullock is a cow.
The characters of castrated individuals are due only to ablation of the sexual glands themselves—the testicles in man and the ovary in woman; mutilation of other sexual organs, internal or external, such as the penis, womb, etc., produces no result of this kind. It would even appear to result from recent experiments that reimplantation of a sexual gland in any part of the body is sufficient to arrest the production of the special peculiarities of the eunuch.
All these facts, almost inexplicable hitherto, become comprehensible by the aid of the engraphia of the mnemic energies. (Vide above; Semon). The sexual glands, being of undifferentiated origin, contain the energies of both sexes. The ecphoria of one of them provokes that of its correlative characters and excludes that of the characters of the other. If ecphoria of the sexual glands is arrested by castration before it is finished, this paralyzes the predominance of that of its corresponding correlative characters and reestablishes a kind of intermediate or undifferentiated equilibrium between the ecphorias of the correlative hereditary sexual characters of the two sexes.
On the other hand, if the sexual glands of an adult are removed, his body is not sensibly modified. The sexual functions do not cease completely, although they cannot lead to fecundation. Men castrated in adult age may cohabit with their wives; but the liquid ejaculated is not semen but only secretion from the accessory prostatic gland. Adult women after castration preserve their sexual appetite, and sometimes even their menstruation, for a certain time. They generally become fat and often suffer from nervous troubles and change in character. The ecphoria of the correlative sexual characters being complete in the adult, suppression of the sexual glands can only act on their direct functions.
In different species of animals, the correlative sexual characters of which we have spoken vary enormously; sometimes the differences are insignificant, at other times they are considerable; while we can hardly distinguish a male swallow from a female, the cock and hen, the peacock and peahen, the stag and hind are very different from each other. In man, the correlative sexual characters are very distinct, even externally. These characters may extend to all parts of the body, even to the brain and mental faculties.
In some of the lower animals, for example the ants, the sexes differ remarkably from each other and appear to belong to different zoological families. The eyes, the form of the head, the color, and the whole body differ so much that, when a case of pathological lateral hermaphrodism is produced (that is, when the sexual glands are male on the one side and female on the other), we can exactly determine the male or female character on each portion of the body. We thus see hermaphrodite ants with one half of the body male and the other half female—black on one side and red on the other, a large eye on one side and a small eye on the other, thirteen joints in one antenna and twelve in the other, and so on. In this case the mental faculties are sometimes female, sometimes male, according as the ecphoria of the brain is influenced by the hereditary mneme of the male or female part of the hermaphrodite sexual organs, which results in a male or female brain. I have seen hermaphrodite ants in which two parts of the thorax formed a crossed hermaphrodism; in front, male on the right and female on the left, behind female on the right and male on the left. Further; among ants which live in societies, the progressive transformation of the species, or phylogeny, has produced a third sex derived from the female sex—the worker; sometimes there is even a fourth—the warrior. In these two forms the wings are absent, but the head and brain are much larger; the sexual organs remain female, but are very small. While the large brain (pedunculated bodies of the supra-esophageal ganglion) is almost rudimentary in the male, it is well developed in the female and very large in the worker and the warrior. Among these singular animals exist pathological hermaphrodites, not only between males and females, but between males and workers, and not only lateral but mixed and crossed in all possible ways. I have seen a hermaphrodite, whose abdomen and sexual organs were almost entirely male, accomplish all the complex instinctive actions of a worker of his species (expeditions, attacks on a hostile ant heap, abduction of chrysalids), thanks to its head and brain which were of the worker type. The female itself is incapable of such complex actions. I cite these facts here as material for study, for we are only too prone in this domain to generalize prematurely and to draw too hasty conclusions. In reality, there is still a wide field for study of the greatest interest.
There are animals which are normally and physiologically hermaphrodite, for they possess in the normal state male and female sexual glands and fecundate themselves, such as the solitary worms, or in pairs such as the snails. In the latter case there is copulation, during which each animal plays the parts of both male and female.
In man and other vertebrates, hermaphrodism is always abnormal. In man it is extremely rare and nearly always very incomplete, being usually limited to the external or correlative characters.
Heredity.—It results from what we have said that every living being reproduces, more or less identically, in its specific characters, the whole life of its parents and less remote ancestors, and constitutes the continuation of life from a minute part of their bodies.
Each individual life thus repeats an entire cycle of development called ontogeny, which is peculiar to all individuals of the species. Here we must mention three fundamental points:
(1). In its principal characters, each individual is the copy of its parents or direct ancestors, with correlative sexual peculiarities which we have mentioned, and with individual variations due to the combinations of varieties by conjugation, and the alternating or unequal ecphorias of hereditary characters; that is to say paternal or maternal hereditary engrams.
(2). No individual is absolutely identical with another.
(3). On the average, each individual resembles more especially its direct ancestry and its parents, and differs more markedly from its parentage the more this is remote.
We shall see later on that the ancestral relationship of the different groups, species and varieties of animals has been fairly well fixed, and we may say that the third of the laws stated above is equally true in a wider sense. In fact the species and varieties of animals which are near related resemble each other, while the genera, families and classes are more dissimilar as their relationship is more remote. We employ here the terms resemblance, homology and difference in their profound and general sense. Certain purely external resemblances, due to phenomena of convergence, must not be considered as homologies in the sense of hereditary relationship. Thus, in the language of natural history we do not say that a bat resembles a bird, nor that a whale resembles a fish, for here the resemblances are due simply to aerial or aquatic life which produces the effects of convergence, while the internal structure shows them to be quite dissimilar organisms. Although it swims in the sea the whale is a mammal; its fins at first sight resemble those of a fish, but they are really the homologues of the four limbs of other mammals and contain the corresponding bones.
In man, we see that brothers and sisters resemble each other in a general way, but that each one is dissimilar in some respects from the others. If we compare different families with many children we find that brothers and sisters resemble each other the more their parents are alike and come from a uniform ancestry which has undergone little crossing, while the crossing of different races and human varieties results in the production of individuals which differ from each other considerably, even when they come from the same couple.
If we examine things more closely, we find that the characters of each of the offspring of the same couple present neither simple repetition nor an equal mixture of the peculiarities of the parents, but very diverse combinations of the characters of several ancestors. For instance, children may bear a striking resemblance to a paternal grandfather, a maternal grand-aunt, or a maternal great-grandmother, etc. This is called atavism. Some children resemble their father, others their mother, and others a kind of mixture of father and mother.
A closer examination reveals further very curious facts. An infant which, in its early years, strongly resembles its father, may later on resemble its mother, or inversely. Certain peculiarities of a certain ancestor appear suddenly, often at an advanced age. It is needless to say that peculiarities concerning the beard cannot appear till this has grown, and this simple fact is so characteristic that it has been called hereditary disposition. Everything may be transmitted by heredity, even to the finest shades of sentiment, intelligence and will, even to the most insignificant details of the nails, the form of the bones, etc. But the combinations of ancestral qualities vary so infinitely that it is extremely difficult to recognize them. Hereditary dispositions arise from the energy of two conjugated germs during the whole of life and till death. Old people sometimes develop peculiarities hitherto unknown in them, owing to the fact that one or more of their ancestors also presented the same phenomena at an advanced age.
Semon has clearly proved that, although forming an infinite number of combinations the engrams or hereditary energies never blend in the proper sense of the term, and in the light of his exposition the above facts are more clearly explained than they had been hitherto. The experiments of Mendel have shown in plants a certain alteration in the hereditary ecphorias of the products of dissimilar parents.
Certain parental characters, according as they are added or subtracted, may disappear during one or two generations, to reappear all the more strongly in the following generations. In short, there are a number of phenomena, the laws of which may be more clearly explained to us in the future.
To sum up, each individual inherits on the average as much from his paternal as from his maternal side, although the minute nucleus of the spermatozoid is the only agent concerned on the paternal side, while the mother provides not only the egg which is much larger, but also nutrition during the nine months of embryonic life. We can only conclude that in the egg also it is only from the part of the nucleus which conjugates with the male nucleus that arise all the inherited maternal peculiarities; that all the rest is only utilized as food; and that the nutritive blood of the mother in no way influences the inherited energies of the offspring.
This shows the capital importance of conjugation and of the substance of the conjugated nuclei, especially of their chromatin. The fact that, in certain of the lower animals, the protoplasm of the egg without nuclei may occasionally produce some phenomena of cell division, thanks to its inherited mnemic engrams, in no way alters the fundamental principle which alone occurs in man, for this vicarious action, which is moreover rudimentary, only happens when the protoplasm of the egg is not consumed by the conjugated nuclei.
Parthenogenesis is also a very interesting phenomenon in the history of our animal ancestors, but for the same reasons it has no direct interest for humanity.
If we take into consideration all the observations of which we have just spoken, which are as simple as they are irrefutably demonstrated, it is hardly possible to interpret them in any other way than by the following hypothesis:
In each sexual gland, male or female, the germinal cells which are produced by division of the cells of the embryo, reserved primarily for reproduction, differ considerably from each other in quality and contain in their infinitely small atoms very diverse and irregularly distributed energies, inherited from their different ancestors. Some contain more paternal and others more maternal energy, and among the former there are some contain, for example, more paternal grandfather and others more maternal grandmother, and so on to infinity, till it is impossible to discover the ancestral origin of the fully grown individual we are examining. The same holds good for the energies of the maternal cells.
At the time of conjugation, the qualities of the child which will result from it depend therefore on conditions of the ancestral qualities of the conjugated egg and spermatozoon. Moreover, although of the same size, the nuclei which become conjugated are evidently of unequal strength; the energies of one or the other predominate later on in the embryo, and still later in man. According to circumstances the latter will resemble more or less his paternal or maternal progenitors.
Moreover, the different organs of the body may receive their energies from different parts of the conjugated nuclei in different degrees. A person may have his father's nose and his mother's eyes, the paternal grandmother's humor and the maternal grandfather's intelligence, and all this with infinite degrees and variations, for it is only a matter of more or less accentuated averages. In my own face the two halves are distinctly different, one resembling my maternal ancestry and the other, in a lesser degree, my paternal ancestry, these points being seen distinctly in photographs taken in profile.
Each germinal cell contains the hereditary mneme of its ancestors, paternal and maternal, and the two cells united by conjugation (Fig. 17) that of the ancestors of each of them. We have spoken above of ecphorias produced according to Mendel's law and reproducing characters which have been latent during one or two generations. Darwin was the first to study this interesting fact, which shows how atavism often results from the crossing of varieties. There are several varieties of fowls which do not brood; if two of these varieties, B and C, are crossed excellent brooders are obtained. Semon assumes that in each of the non-brooding varieties the ancestral energy, A, of the primary species, is weaker than that of varieties B and C; we have then A > B, and A < C. But if B is coupled with A the product represents the value B + C + A + A. Then B and C are in equilibrium; and A being doubled becomes stronger than each of them and arrives at ecphoria in their place, which restores the faculty of brooding to the product of crossing.
De Vries has shown, in the crossing of varieties with their primary species, more or less analogous phenomena which he calls "Vicino-variations." Conjugation leads to infinite combinations and variations which the law of heredity traverses like a guiding line.
The celebrated zoologist, Weismann, considers that the chromatin of each germinal cell contains a considerable quantity of particles each of which is capable of forming an entire organism similar to the parents; these he calls "ides." According to Weismann, each ide is subdivided into "determinants" from which each part of the body is derived, being potentially predetermined in them. According to the action of a yet unknown irritation male or female determinants develop in each individual of the animal species with separate sexes. But if the determinants are disordered, either by abnormal variations or by pathological causes, hermaphrodites or monstrosities may be produced. In animals which are normally hermaphrodite (snails, etc.), there is only one kind of sexual determinant, while in polymorphous animals (ants, etc.), there are as many as the polymorphous forms. The conception of "ides" and "determinants" is only a hypothesis to which we must not attach much value. The mnemic laws established by Semon give a much better explanation of the facts.
It has often been maintained that the qualities of higher forms of man are exhausted in a few generations, while the mass of mediocrities continually produce new genius. The fact that the descendants of distinguished men are often mediocre and that remarkable men suddenly arise from the common people, appears at first sight to support this superficial assertion. It is forgotten, however, that in a people whose average mass consists of thousands or millions of individuals, while men of higher powers are only counted by units or dozens, all this arithmetic is reduced to absurdity by the inequality of numbers, as soon as the law of heredity is understood. To make a more exact calculation, it would be necessary to compare the number of superior men who have arisen from some hundreds of the most distinguished families of a country with that of distinguished men who have arisen from some millions of the rest of the people, and then calculate the percentage. It is also necessary to take into account the means employed in the education of the individuals. If education is obligatory and gratuitous in a country, this factor will have less importance.
Another error which is committed in such cases is to neglect the influence of the maternal lineage. A common woman will lower the level of the offspring of a distinguished husband, and inversely. In his "History of Science and Scientists" Alphonse de Candolle has given irrefutable proof that the posterity of high-class men furnishes a great number proportionally of men high class in their turn, compared with that of the average population. This shows the value of the usual twaddle concerning this question. It is inconceivable that the laws of heredity should make an exception of the mental qualities of man. Moreover, the most deceptive point is the contrast of a man of genius with his children, who do not rise to his standard because they represent a combination of his ancestral energies with those of their mother. This contrast makes the children appear unfavorably, while the public has a general tendency to exaggerate the value of a great man.
The theory of the mneme throws light on this subject, by introducing a new factor in the question, that of ecphoria of the cerebral engrams of the ancestors, accumulated in the hereditary mneme.
Heredity of Acquired Characters.—While Darwin and Haeckel affirmed the possibility of the heredity of characters acquired during life by different tissues, for instance the brain, Weismann limits the possibility to everything that can modify the nucleoplasm of the germinal cells. We must first eliminate the question of the phenomena of blastophthoria, which we shall consider next, and which Weismann was, I think, the first to comprehend, without giving them the name.
On one hand we see the singular effects of castration, which we have already considered; on the other hand, an extraordinary constancy in the hereditary characters of the species. For more than three thousand six hundred years, which corresponds to about eight hundred generations, the Jews have been circumcised. Nevertheless, if a Jew ceases to circumcise his offspring the prepuce of his children grows as it did three thousand six hundred years ago, although, during the eight hundred generations in question, its absence from birth has prevented it reacting on the germinal cells of the individuals. If the engraphia of the external world could sensibly modify in a few generations the hereditary mneme of the species, it appears evident that the Jewish infants of the present day would be born without prepuce, or at least with an atrophied one.
It is on such facts, which are innumerable in natural history, that Weismann relies to repudiate absolutely the heredity of characters acquired by non-germinal organs and to attribute the development of organisms to blends and combinations due to conjugation, or crossing, as well as to natural selection, which he regards as all-powerful. Darwin well recognized the difficulty in question, and being unable to explain the facts, had recourse to the hypothesis of pangenesis, that is of small particles detached from all parts of the body and transported by the blood to the germinal cells, to transmit to them, for example, the qualities acquired by the brain during life. This hypothesis was so improbable that Darwin himself was forced to recognize it. Let us examine the facts.
On the one hand a newly born Chinese transported and brought up in France will learn French, and will show no inclination to learn or understand Chinese. This well-established fact seems in favor of Weismann and against the heredity of acquired characters. But, on the other hand, we cannot understand how the evolution of the brain and its functions takes place, without admitting that in one way or another the characters acquired by habits repeated during many generations gradually accumulate in the form of hereditary dispositions in the germinal protoplasm. It is certain that our brain has progressed since the time when our ancestors were similar to the gorilla, or even the cave man at the beginning of the quaternary age. How can this cerebral progression be explained only by selection which can only eliminate, and by crossings which by themselves can hardly raise the average? It is here that the intervention of an unknown power is necessary, something unexplained, the action of which has been lately recorded in the phenomena of mutations of de Vries.
De Vries proves that certain variations appear suddenly and without any known cause, and have a much greater tendency to be preserved than the variations obtained by crossing and selection. In my opinion the phenomena of the mneme revealed by Hering and Semon explain the apparent contradictions which have hitherto impaired the theories of heredity. Mnemic engraphy explains, by its infinitesimal and repeated action through numerous generations, how the external world may little by little transmit to the germinal cells the characters which it impresses on organisms. The eight hundred generations during which the prepuce of the Jews has been cut off have not yet sufficed for the ecphoria of the corresponding negative mnemic engraphia; while conjugation and selection modify rapidly and strongly in a few generations; a fact which is more striking and allows of direct experiment. Moreover, a positive engraphia must necessarily act more powerfully, and it seems to me that mutations must be the ecphoria of accumulated former latent engraphias.
Merrifield and Standfuss, by exposing caterpillars and chrysalids for varying periods to considerable degrees of cold and heat, have determined permanent changes in the specific characters of the butterflies which have emerged from them.
Standfuss and Fischer have also shown that, after several generations, by continuing the action of cold on the caterpillars, the variations thus produced can be preserved even after the cold has ceased to act. No doubt the cold acts on the germinal cells as on the rest of the body, but the heredity of an acquired character is thus demonstrated.
The experiments of Miss de Chauvin on salamanders (Axolotl) are still more conclusive, for we are dealing here with characters acquired through aquatic or aerial media, which can hardly act on the sexual glands. We cannot continue this subject any further and we return to the work of Semon. It is needless to say that the nature of mnemic engraphia remains itself an unknown quantity. As long as we are unable to transform inert matter into a living organism we shall remain in ignorance. But, when it is accepted with the laws of the phenomena which it produces, this unknown quantity, as Semon has shown, alone suffices to explain all the rest, and is already a great step toward the comprehension of the laws which govern life.
Blastophthoria.—By blastophthoria, or deterioration of the germ, I mean what might also be called false heredity, that is to say, the results of all direct pathogenic or disturbing action, especially that of certain intoxications, on the germinal cells, whose hereditary determinants are thus changed. Blastophthoria thus acts on germs not yet conjugated, through the medium of their bearers, and creates at their origin hereditary stigmata of all kinds, while true heredity only combines and reproduces the ancestral energies.
Blastophthoria deranges the mneme or hereditary engrams, and consequently a more or less considerable part of their ecphorias during the life of the individuals which arise from them. It is not a question here of the reproduction of the hereditary ancestral energies in the descendants (in different combinations) as is the case in the heredity which we have just studied, but, on the contrary, a question of their perturbation. However, the store of cells reserved as germinal cells in the embryo, the germ of which has been damaged by blastophthoric action, being usually also affected by the disturbing cause, it follows that the pathological change introduced by blastophthoria in the hereditary mneme is transmitted to the descendants by ordinary heredity. In this way blastophthoria deposits the first germ of most pathological degenerations by causing immediate deviation of all the determinants of the germ in the same direction.
The most typical and the commonest example of blastophthoria is that of alcoholic intoxication. The spermatozoa of alcoholics suffer like the other tissues from the toxic action of alcohol on the protoplasm. The result of this intoxication of the germs may be that the children resulting from their conjugation become idiots, epileptics, dwarfs or feeble minded. Thus it is not alcoholism or the craving for drink which is inherited. No doubt the peculiarity of badly supporting alcohol is inherited by ordinary heredity as a hereditary disposition, but it is not this which produces the alcoholic degenerations of the race. These are the result of the single blastophthoria. When, on the other hand, a man is found to be imbecile or epileptic as the result of the insobriety of his father, he preserves the tendency to transmit his mental weakness or his epilepsy to his descendants, even when he abstains completely from alcoholic drinks. In fact, the chromosomes of the spermatozoid, from which about a half of his organism has issued, have preserved the pathological derangement produced by the parental alcoholism in their hereditary mneme, and have transmitted it to the store of germinal cells of the feeble minded or the epileptic, who in his turn transmits it to his descendants. From Weismann's point of view his hereditary determinants remain pathologically deviated. All intoxications which alter the protoplasm of the germinal cells may produce blastophthoric degenerations, which continue to menace several successive generations in the form of hereditary taints.
Other deviations in the development of the germs may act in an analogous manner to blastophthoria. We have mentioned above the experiments of Merrifield and Standfuss on the caterpillars of certain butterflies. Without being really of a pathological nature, these actions of a physical agent on the hereditary energies resemble blastophthoria.
Mechanical action on the embryo may also give rise to pathological products or even mutilation. Thus, Weismann demonstrated the production of degenerate individuals in ants when certain coleoptera were introduced in their nest, the ants being fond of the secretion of the large glandular hairs of the coleoptera. The exact cause of the degeneration has not yet been found, but the fact is certain. In man, certain constitutional affections and congenital anomalies are the result of certain diseases in the procreators, which have affected the germinal cells or the embryo (for instance syphilis). As soon as the blastophthoric actions cease in the procreators, those of their descendants who live under a normal regimen have evidently a tendency to eliminate the blastophthoric organs at the end of several generations and to regenerate themselves little by little. Thanks to the power of the ancestral mneme which tends to reestablish homophony. However, the data on this subject are insufficient. In this case homophony is represented by the normal equilibrium of the different typical or normal characters of the species.
 I insert here some passages intended for more advanced readers, but this does not imply that they are of less importance. On the contrary I strongly advise all my readers to try and understand the theories of Hering and Semon, which appear to me to throw a new light on the question of transformation and heredity.
EVOLUTION OR DESCENT OF LIVING ORGANISMS
The theory of evolution is intimately associated with the name of Darwin, for it was he who established it in the scientific world. In reality, the idea of the transformation of organisms was put forward by Lamarck more than a century ago, but he did not sufficiently support it. The theory of evolution states that the different animal and vegetable species are not each of them specially created as such from the first, but that they are connected with each other by a real and profound relationship, and derived progressively one from another; generally from more simple forms, by engraphia and selection. Man himself is no exception to this rule, for he is closely related to the higher apes.
It is no longer possible to-day to deny the fundamental fact which we have just stated. Since Darwin, and as the result of the powerful impulse which this man of genius gave to natural science, innumerable observations and experiments have confirmed the truth of the progressive evolution of living beings. Comparative anatomy, comparative geography of plants and animals, comparative embryology, and the study of the morphology and biology of a number of recently discovered plants and animals, have built up more and more the genealogical tree, or phylogeny, of living beings, that is to say their ancestral lineage. The number of varieties and races or sub-species increases indefinitely, the more closely they are examined.
Researches on the fossil remains of species of animals and plants which have been extinct for thousands and millions of years (palaeontology) have also contributed to determine the trunk of the great tree of former life. The numerous gaps which still exist between these fragmentary documents of former ages are nevertheless too considerable for continuous connections to be established in the past by the aid of fossils.
We not only know that the different forms of living beings are connected to each other by a real relationship, but we can fathom more and more deeply the degrees of this relationship, and can often prove from which group of animals a given group is descended. In many cases we can determine at which period the fauna and flora of two continents have been separated from each other, and in what manner they have been transformed, each in its own way, while still preserving the general characters which were common before their separation. The specialist can soon discover what species belong to the old geographically differentiated fauna and flora of the country, and what have been ulteriorily imported.
I record these facts for the benefit of those persons who have not yet understood that it is absolutely useless at the present day to dispute the evolution of living beings. Deceived by the divergent opinions of scientists concerning hypotheses which endeavor to explain the details of evolution, these persons confound the details with the fundamental facts of evolution.
Ontogeny. Phylogeny.—In the light of the facts of evolution, heredity takes quite a new aspect when removed from the old biblical idea of the independent creation of species. Haeckel launched into the scientific world, under the name of "fundamental biogenetic law," a theory which, without having the right to the title of an immutable dogma, explains the facts in a general way, and gives us a guiding line along the phylogenetic history of living beings. "Ontogeny," that is the history of the embryological development of each individual, always consists in a summary and fragmentary repetition of phylogeny, or the history of the ancestors of the species to which the individual belongs. This signifies that, as embryos, we repeat in an abridged form the series of types or morphological stages through which has passed the series of our animal ancestors, from the primitive cell to man. In reality this is only true in a relative way, for a considerable part of the ancestral engraphias of the embryo has disappeared without leaving any trace; also many embryos, especially those which have special conditions of existence outside the body of their mother, have acquired special complex organs and corresponding functions. Thus, the caterpillars of butterflies with their specific and generic peculiarities, hairs, horns, etc., furnish many examples of secondary acquired characters which have nothing in common with the worm, which is the ancestral type of the butterfly represented by the embryonic period when it is a caterpillar. However, many undoubted vestiges of the ancestral history are found in the embryos at different periods of their development. It is certain that insects descended from worms, and there is no doubt that the larvae of insects, which are almost worms, represent the ontogenetic repetition of the phylogeny of insects.
It is also certain that whales, although they have whalebone instead of teeth, have descended from cetacea provided with teeth, which in their turn descended from terrestrial mammals. But we find in the embryo whale a complete denture which is of no use to it, and which disappears in the course of the embryonic period. This denture is nothing else than a phylogenetic incident in the ontogeny of the whale.
In the fins of cetacea, as in the four limbs of other mammals, we find the same bones, which are derived from the bones of the wings and legs of their bird ancestors. In birds, the same bones are the phylogenetic derivatives of the limbs of reptiles.
All these facts demonstrate with certainty the descent of animal forms, a descent which we can follow in all its details. In certain ants whose bodies show their close relationship with a slave-keeping group, but which have become the parasitic hosts of other ants, we find not only the arched mandibles, shaped for rape, but the undoubted rudiments of the slave instinct, although this instinct has, perhaps, not been exercised by them for thousands of years.
These examples suffice to show that the form and functions of a living organism, as well as its mental faculties, are derived not only from the most recent direct ancestors of this organism, but that they partly mount much higher in the genealogical tree.
Our coccyx is a vestige of the tail of animals. It is from them also that we have inherited anger and jealousy, sexual appetites, fear, cunning, etc. As long as they remain in use, the oldest inherited characters normally remain the most tenacious and are preserved the longest. When they cease to be utilized, or become useless, they still remain for a long time as rudiments before finally disappearing; for instance the vermiform appendix of the intestine and the pineal gland of the brain. These rudiments often persist for still a longer time in the embryo, as we have seen in the case of the ancestral teeth of the embryo whales. We also meet with the stumps of wings in the chrysalis of certain ants (Anergates), the males of which have lost their wings.
Natural Selection.—The artificial selection practiced by gardeners and cattle breeders led Darwin to his hypothesis of natural selection by the struggle for existence. Confirmed in his idea by the observation of tropical nature, Darwin thought he could explain the origin of living beings by natural selection. It is this hypothesis which is properly called Darwinism. But the name Darwinism has also been given to evolution as a whole, which has been the cause of endless confusion. All the mystic and narrow-minded, full of biblical prejudice, naturally profit by this confusion to attack the facts of evolution and science itself.
The Struggle for Existence.—The struggle for existence and natural selection are absolutely positive facts, which can be constantly verified by the observation of living nature as it is presented to us. All living beings eat one another or at any rate struggle against each other, plants as well as animals; and, apart from air and water, animals are almost entirely nourished by plants and other animals. It is obvious that in this perpetual struggle the less adapted and the less armed—and by arms we include the powers of reproduction, resistance to diseases and to cold, etc.—disappear, while the better adapted and the better armed persist. I confess I cannot understand the detractors of Darwin who are blind in face of these facts and hypnotized by certain conventional suggestions.
On the other hand, what always has been and still remains hypothetical is the explanation of the descent of all plants and animals by natural selection alone. We have already spoken of the mutations of de Vries, and the theory of the mneme elaborated by Semon, and need not repeat them here. Thanks to the idea of Hering, worked out by Semon, the facts are now explained in a satisfactory manner. Engraphia, produced in the organisms by the irritating agents of the external world, prepares and builds up little by little their increasing complications, while selection, by continually eliminating the unfit, directs the elaborating work of the mneme and adapts it to the surrounding local circumstances.
De Vries has objected that the variations produced by artificial and natural selections are mutable, while sudden mutations have a much more stable character. But we have just seen that these mutations themselves are evidently only the delayed ecphoria of a long ancestral engraphia accumulated.
On the other hand, the variations obtained by selection are themselves only due to more rapid ecphorias, derived from repeated conjugations in a certain direction. Plate and others have shown that they may become more and more fixed, if they are well adapted, and thus become more tenacious. There is, therefore, no contradiction between the fundamental facts, and all is simply and naturally explained by the combination of hereditary mnemic engraphia with selection.
Recent study on the transformations of living beings have shown that they do not take place in a regularly progressive manner, as Darwin at first believed, but that periods of relatively rapid transformation alternate with periods of relative arrest, both in a general way and for each particular species. We see certain species remaining almost stationary for an immense time and tending rather to disappear, while others vary enormously, showing actual transformation. The transplantation of one species to a new environment, for instance to a new continent, provokes, as has been proved, a relatively rapid transformation. It is evident that mnemic engraphia transforms organisms the more rapidly as it changes in nature itself, which is the case in the migrations we have just mentioned, and which also changes the factors of selection.
Other facts show clearly that the fauna and flora of the present world find themselves in a period of recoil with regard to their modification. In the tertiary period the fauna and flora of the world were richer than to-day; many more older species have disappeared than new ones have arisen. This fundamental fact seems due to the extremely slow cooling of the earth, and appears to be indicated by the powerful growth in tropical climates, the fauna and flora of which resemble those of the tertiary period, and, on the other hand by the relative poverty and slowness of growth in cold countries.
Conclusions.—What are the principal conclusions to which we are led by this short study of the ancestral history or phylogeny of man?
(1). The transformation or evolution of living beings is a demonstrated fact.
(2). The factors in evolution appear at first sight to be very diverse: selection, mutation, climatological, physical and chemical factors, etc.
We have seen that they may all be connected with the fundamental principle of mnemic engraphia, aided by natural selection. No doubt the nature of the mnemic engraphia of external agents in the living substance is still unknown. When we are able to connect the laws of life with the laws of inert nature, we shall only have before us a single great metaphysical mystery, that of the tendency of mundane energy to the differentiation of details and the production of complicated forms. What is important here is to know that engraphia and selection are capable of considerably modifying species in a positive or negative manner, for good or evil, improving them by good influence and good conjugations, or deteriorating them by bad selection or by blastophthoria, which causes them to degenerate. The combination of a bad selection with blastophthoric influences constitutes the great danger for humanity, and it is here that a rational sexual life should intervene.
(3). The mental faculties of animal species, as well as their physical characters, depend on their ancestral hereditary mneme. They simply represent the internal or introspective side of central activity, and the brain obeys the natural laws of the mneme in the same way as the other organs.
(4). It follows from all this that phylogeny and selection, the same as heredity properly understood, have the right to a fundamental place in the sexual question, for the germs which, after each conception, reproduce an individual are, on the one hand, bearers of the inherited energy of our ancestors, and on the other hand, that of future generations. According to the care or neglect of civilized humanity they may be transformed for good or evil, progress or recede. Unfortunately, owing to religious and other prejudices, the question of evolution is not discussed in schools. Hence, the majority of men only hear of these things by hearsay in a rough and inexact manner; so that a series of phenomena familiar to naturalists and medical men, are still dead letters for the rest of the public. This obliges me to speak further on some points of detail.