Mac Donald.

Stature of normal persons

Stature of abnormal persons

Fig. 35.

But we are too far removed from the triumphant civilisation of Greece, to recur to the authority of her example: the principle sanctioned to-day by modern civilisation, that of "respect for human life," forbids the violent elimination of the weak: Mount Taygetus is no longer a possible fate for innocent babes in a social environment the civic spirit of which has abolished the death penalty for criminals. Consequently, since the weak have a right to live, as many of them as naturally survive are destined to become a burden, as parasites, upon the social body of normal citizens; and they furnish a living picture of physiological wretchedness, a spectacle of admonitory misery, inasmuch as it represents an effect of social causes constituting the collective errors of human ethics. Ignorance of the hygiene of generation, maladies due to the vices and the ignorance of men, such as syphilis, other maladies such as tuberculosis, malaria and pellagra, representing so many scourges raging unchecked among the people, are the actual causes that are undermining the social structure, and manifesting themselves visibly through their pernicious fruit: the birth of weaklings. To forget the innocent results of such causes, as we forget the causes themselves, would be to run the risk of plunging precipitously into an abyss of perdition. It is precisely these disastrous effects upon posterity that ought to warn us and shed light upon the errors through which we are passing lightly and unconsciously. Accordingly, to gather in all the weaklings is equivalent to erecting a barrier against the social causes which are enfeebling posterity: since it is impossible to conceive that if the existence of such a danger were once demonstrated, society would rest until every effort had been made to guard against the possibility of its recurrence.

In addition to such motives for human prophylaxis, a more immediate interest should lead us to the pedagogic protection of weak children. The establishment of special schools for defective children, sanatarium-schools for tuberculous children, rural schools for those afflicted with malaria and pellagra, infant asylums for rachitic children, is a work of many-sided utility. They constitute a fundamental and radical purification of the schools for normal children: in fact, so long as intellectual and moral defectives and children suffering from infantilism and rachitis intermingle with healthy pupils, we cannot say that there really exist any schools for normal children, in which pedagogy may be allowed a free progress in the art of developing the best forces in the human race.

Still another useful side to the question is that of putting a stop to the physiological ruin of individual weaklings. Very small would be the cost of schools for defective children, asylums for the rachitic, tonics, quinine, the iodide treatment, school refectories for little children afflicted with hereditary taints and organic disease: very small indeed, in comparison to the disastrous losses that society must one day suffer at the hands of these future criminals and parasites gathered into prisons, insane asylums and hospitals, in comparison to the harm that may be done by one single victim of tuberculosis by spreading the homicidal bacilli around him. It is a principal of humanity as well as of economy to utilise all human forces, even when they are represented by beings who are apparently negligible. To every man, no matter how physiologically wretched, society should stretch a helping hand, to raise him. In North America the following principle has the sanction of social custom: that the task of improving physiological conditions and at the same time of instilling hope and developing inferior mentalities to the highest possible limit constitutes an inevitable human duty.

Accordingly it remains for the science of pedagogy to accomplish the high task of human redemption, which must take its start from those miracles that the twentieth century has already initiated in almost every civilised country: straightening the crippled, giving health to the sick, awakening the intelligence in the weak-minded—much as hearing is restored to the deaf and speech to the mutes—such is the work which modern progress demands of the teacher. Because such straightening of mind and body naturally lies within the province of those who have the opportunity to give succor to the human being still in the course of development; while after a defect has reached its complete development in an individual, no manner of help can ever modify the harm that has resulted from lack of intelligent treatment.

The prevention of the irremediable constitutes a large part of the work which is incumbent upon us as educators.

Summary of Stature

We have been considering stature as the linear index of the whole complex development of the body, taking it in relation to two other factors, the one internal or biological, and the other external or social. These two factors, indeed, unite in forming the character of the individual in his final development; and in each of them education may exert its influence, both in connection with the hygiene of generation and through reforms instituted in the school.

In the following table are summed up the different points of view from which we have studied stature in its biological characteristics and in its variations:

Summary of the Scientific Principles Illustrated in The Course of the Exposition of Our Subject

When an anthropological datum is of such fundamental importance as the stature, its limits of oscillation must be established, and its terminology must be founded upon such limits expressed in figures that have been measured and established by scientists (medium, tall, low).

The stature is the most important datum in pedagogic anthropology, because it represents the linear index of the development of the body, and for us educators is also the index of the child's normal growth.

Biopathological Laws.—In cases of total arrest of development of the personality (infantilism) the first characteristic symptom usually consists in a diminution of stature in relation to age; the morphological evolution, as well as the psychic, fails to progress in proportion to the age of the subject; but it corresponds to the mean bodily proportions belonging to the age which would be normal for the actual stature of the subject.

Weight

The weight is a measure which should be taken in conjunction with the stature; because, while the stature is a linear index of the development of the body, the weight represents a total measure of its mass; and the two taken together give the most complete expression of the bio-physiological development of the organism.

Furthermore the weight permits us to follow the oscillations of development; it provides educators with an index, a level of excellence, or the reverse, of their methods as educators, and of the hygienic conditions of the school or of the pedagogic methods in use.

The fact is, that if a child is ill, or languid, etc., his stature remains unchanged; it may grow more slowly, or be arrested in growth; but it can never diminish. The weight, on the contrary, can be lost and regained in a short time, in response to the most varied conditions of fatigue, of malnutrition, of illness, of mental anxiety. We might even call it the experimental datum of the excellence of the child's development.

Another advantage which the measure of weight has over that of stature is that it may serve as an exponent of health from the very hour of the child's birth; while stature does not exist in the new-born child, and begins to be formed (according to the definition given) only after the first year of its life, that is, when the child has acquired an erect position and the ability to walk steadily.

Variations.—Weight is one of the measures that have been most thoroughly studied, because it is not a fruit of the recently founded science of pedagogic anthropology; but it enters into the practice of pediatricians (specialists in children's diseases) and of obstetricians (specialists in childbirth), while even the general practitioner can offer precious contributions from his experience.

According to Winckel, and practically all pediatricians agree with him, "the weight of a child, if taken regularly, is the best thermometer of its health; it easily expresses in terms of figures what the nursing child cannot express in words."[34]

The new-born child weighs from three to four kilograms; but oscillations in weight from 2,500 to 5,000 grams are considered normal. Some obstetricians have noted weights in new-born children that are enormous, true gigantism, which, however, while possible, are altogether exceptional; nine and even eleven kilograms.

The oscillations in weight of the child at birth, within normal limits, may have been determined by general biological factors, as for example the sex (the female child weighing less than the male), and the race (especially in regard to the stature of the parents): but the factors which influence the weight of the new-born child in a decisive manner are those regarding the hygiene of generation.

1. "The children which have the greater weight are those born of mothers between the ages of twenty-five and thirty." (Mathews Duncan.) Let us recall what we have said regarding stature; at the end of the twenty-fifth year, that is, at the end of the period of growth, man is admirably ripe for the function of reproduction; and we ought further to recall the views cited regarding the mortality of children conceived at this age which is so favourable to parenthood; and finally the note in regard to celebrated men, almost always begotten at this age.

2. "First-born children have in general a weight inferior to that of those born later (1,729 first-born children gave an average of 3,254 grams: while 1,727 born of the second or subsequent conceptions gave an average of 3,412 gr.)" (Ingerslevs). Let us remember that celebrated men are scarcely ever the first-born.

3. "Very short intervals between successive pregnancies interfere with this progression in weight; long intervals on the contrary do not interfere with it" (Wernicke). In other words, too frequent pregnancy is unfavourable to the result of the conception.

4. "Mothers who, at the birth of their first child weigh less than fifty-five kilograms and are under twenty years of age, have children of inferior weight, who are less predisposed to normal growth" (Schafer).

Let us recall what we have said regarding the form and the scanty weight in the case of macrosceles; and also in regard to the age of procreation in its relation to stature.

5. "Women who toil at wearisome work up to the final hour give birth to children inferior in weight to those born of mothers who have given themselves up to rest and quiet for some time before the expected birth" (Pinard).

All these considerations which refer to normal individuals, represent a series of hygienic laws regarding maternity, which may be summed up as follows: excellence in procreation belongs to those mothers who have already attained the age at which the individual organism has completed its development, and before it has entered upon its involutive period; the mother must herself have a normal weight; the pregnancies must be separated by long intervals; and during the last weeks of pregnancy it is necessary that the mother should have the opportunity of complete rest.

The increase in weight of the new-born child during the first days of its life, may constitute a valuable prognostic of the child's life. That is to say, through its successive gains it reveals the vitality, the state of health of this new human being.

Here also the pediatrists can furnish us with valuable experimental data, which serve to formulate the "laws of growth." These are:

1. From the moment of a child's birth, throughout the first two days, it suffers a loss in weight of about 200 grams, due to various causes, such as the emission of substances accumulated in the intestines during the intrauterine life (meconium), and the difficulties of adaptation to a new environment and to nutrition. But by the end of the first week a normal child should have regained its original weight; so that after the seventh day the normal child weighs the same as at the moment of birth.

On the contrary, children born prematurely, or those having at the time of birth a weight below the average, or those that are affected with latent syphilis, or are weak from any other cause whatever, regain their original weight only by the end of the second week.

Accordingly, in one or two weeks the family may form a prognosis regarding future life of the new-born child: a matter of fundamental and evident importance.

Furthermore, an antecedent detail of this sort may be valuable in the progressive history of subjects who, having attained the age for attendance at school, come to be passed upon by the teachers.

To this end, in the more progressive countries, the carnet maternel, or mother's note-book, has begun to come into fashion, for the use of mothers belonging to the upper social classes (as, for instance, in England): it consists of a book of suitable design, in the form of an album, and more or less de luxe in quality, in which the most minute notes are to be registered regarding the lives of the children from the moment of their birth onward. Various authors, especially in France, now give models for the maternal registration of the child's physiological progress; true biographic volumes that would form a precious supplement to the biographic charts of the schools: and the efforts of the family would round out and complete those of the school for the protection of the lives of the new generations. Such assistance, however, is only an ideal, because nothing short of a great and far distant social progress could place all mothers (the working women, and the illiterate of Italy) in a position to compile their carnet maternel. Auvard advocates, for registering the weight of the child during the first days of its life, a table in which the successive days from the first to the forty-fifth are marked along a horizontal line, while a vertical column gives a series of weights, with 25-gram intervals, covering a range of 700 grams, the multiples of a hundred being left blank, to be determined by the actual weight of the child and filled in by the mother or whoever takes her place.

Fig. 36.

In such a table, the graphic sign indicating the changes in weight ought to fall rapidly and rise again to the point of departure by the seventh day, if the child is robust.

Another law of growth which may serve as a prognostic document in the child's physiological history is the following:

2. "Children nourished at their mother's breast double their weight at the fifth month and triple it at the twelfth." In other words, before the middle of its first year a healthy child, normally nourished, will have doubled its weight.

On the contrary, "Artificial feeding retards this doubling of weight in children, which is attained only by the end of the first year; so that the weight is not tripled until some time in the course of the second year."

And this gives us pretty safe principles on which to judge of the personality in the course of formation, at an epoch when stature does not yet exist.

Undoubtedly a great moral and social progress would be accomplished through a wide dissemination of very simple and economical carnets maternels; which should contain not only tables designed to facilitate the keeping of the required records, but also a statement of the laws of infant hygiene; or at least, simple and clear explanations of the significance of such phenomena, in relation to the life and health of the child; and also as to the causes which produce weakness in new-born children; or in other words, advice regarding the fundamental laws of the hygiene of generation. All that would be needed, in such case, would be a progressive exposition by means of the carnets, through lessons made as simple and as objective as possible, such as the weighing of small babies, to make the much desired "education of the mothers" both possible and practical.

But without this practical means; without this new sort of syllabarium on hand, to serve as a constant and luminous guide for married women, I do not believe that we shall have much success with the scattered lectures, obscure and soon forgotten, that at present are being multiplied in an attempt to reach the mothers of the lower classes.

In conclusion, I note this last contribution that comes to us from the pediatrists:

3. "There are certain maladies that cause a daily and very notable loss in weight"; they are the intestinal maladies; there may be an average loss of from 180 to 200 grams a day; but even in cases of simple loss of appetite (dyspepsia) the weight may decrease by about 35 grams a day. But when a child suffering from acute febrile intestinal trouble (cholera infantum), loses a tenth of his weight in twenty-four hours, the illness is mortal.

Now from the point of view of the educator this fact ought to be of serious interest, because we very frequently find among the recorded details of sickly children, or those suffering from arrested or retarded development, a mention of some intestinal malady incurred in early infancy.

Still one further observation: Meunier has noted a fact of extreme importance: that while children are passing through the period of incubation of an infectious disease, and before they show any symptoms likely to cause a suspicion of the latent illness, they sustain a daily loss in weight, from the fourth or fifth day after exposure to contagion until the appearance of decisive symptoms. In children between one and four years old, the daily loss is about fifty grams, and the total about 300; but such a loss may rise as high as 700 gr. The most numerous observations were taken in cases of measles.

Now, there is no need of explaining the prophylactic importance of observations such as these! A child who for a period of twenty days is in a state of incubation, is called upon to struggle, with all the forces of immunity that his organism possesses, against a cause of disease which has already invaded him; yet no external sign betrays this state of physical conflict. Consequently, the child's organism continues to sustain the customary loss of energy due to the activities of its daily life, and by doing so lessens its own powers of immunity. To prescribe rest, if nothing more, for a child suspected of passing through the period of incubation would in many cases mean the saving of a life, and at the same time would protect his companions from infection, which is communicable even during the period of incubation.

In our biographic records of defective children, which include the great majority of the weakly ones, we find in many cases a characteristic tendency to relapses in all kinds of infective diseases, from which they regularly recovered. Such organisms, feeble by predisposition, yet sufficiently strong to recover from a long series of illnesses, were exhausted in respect to those biological forces on which the normal growth of the individual depends, by this sort of internal struggle between the organic tissues and the invading microbes. No scheme of special hygiene for children of this type can help us, either in the home or at school; the daily variations in weight, on the contrary, might constitute a valuable guide for the protection of such feeble organisms; at the first signs of a diminution in weight, such children ought to be subjected to absolute repose.

The use of the weighing-machine, both at home and in school cannot be too strongly recommended. In America the pedagogic custom has already been established of recording the weight of the pupils regularly once a month; but instead of once a month, the weight ought to be taken every day. The children might be taught to take their own weight by means of self-registering scales, and to compare it with that of the preceding day, thus learning to keep watch of themselves: and this would constitute both a physical exercise and an exercise in practical living.

The weight may be considered by itself, as a measurement of the body; and it may be considered in its relation to comparative mean measurements given by the authorities; just as it may also be considered, in the case of the individual, in its relation to the stature.

a. The weight, taken by itself, is not a homogeneous or rigorously scientific measurement. In the same manner as the stature, it represents a sum of parts differing from one another, the difference in this instance being that of specific gravity. As a matter of fact, it makes a great difference whether a large proportion of the weight of an individual is adipose tissue, or brain, or striped muscles. Each of the various organs has its own special specific gravity, as appears from the following table:

All these specific gravities are low; we weigh but little more than water; and for that reason it is easy for us to swim. But because of the difference in their composition, the total weight of the body gives us no idea of its constituent parts.

Take for example the question of increase in weight. We can compare the mean figures given by the authorities with the ascertained weight of some particular child of a given age, so as to keep an empirical check upon the normality of its growth. But since we know that an individual in the course of evolution undergoes profound alterations in the volumetric proportions of the different organs in respect to one another, we cannot obtain from the total weight any light upon this extremely important alteration in proportions. Thus, for example, Quétélet gives the following figures of increase in weight for the two sexes:

INCREASE IN WEIGHT OF BODY
According To Sutils

But these figures give no idea of the laws of growth that govern each separate organ, and that have been studied by Vierordt. According to this authority, the total weight of the body increases nineteen-fold from birth to complete development. Certain ductless glands, on the contrary, diminish in weight in the course of growth; the thymus, for instance, is reduced to half what it weighed originally.

Furthermore, the various organs all differ in such varying degrees, as compared with their respective weights at birth, that it facilitates comparison to reduce the weight of each separate organ to a scale of 1. On this basis we find that when complete development is attained, the eyes weigh 1.7; the brain 3.7; the medulla oblongata (spinal marrow) 7; the liver 13; the heart 15; the spleen 18; the intestines, stomach and lungs 20; the skeleton 26; the system of striped muscles 48.

And these widely different augmentations are not uniform in their progress, nor is the complete development of each organ attained at the same epoch. As a matter of fact, the brain acquires one-half its final weight at the end of the first year of age; the organs of vegetative life attain half their weight at the beginning of the period preceding puberty (eleventh year). To offset the lack of indications regarding such increases in weight, we have a guide in the morphology of growth, which reveals how differently the various parts of the body develop.

However empirical it may be from an analytical point of view, the datum of weight is a valuable index, and represents, taken by itself, a synthetic anthropological measure of prime importance.

It obeys certain laws of growth which are themselves of great interest; namely, there exist two periods of rapid growth: at birth and during puberty; while at various periods in childhood, between the ages of three and nine, there are alternations of greater and lesser growth analogous to those already noted in relation to stature.

Accordingly, the weight confirms the fact that the organism does not proceed uniformly in its evolution, but passes through crises of development during which the forces of the organism are all devoted to its rapid transformation; such periods represent epochs at which the organism is more predisposed to maladies, more subject to mortality and less capable of performing work (compare the observations already made in relation to stature).

Index of Weight.—Accordingly, weight and stature stand in a certain mutual relationship, but the correspondence between them is not perfect. In the study of individual physiological development it is necessary to know the anthropological relation between weight and stature; in other words, the ponderal index. Without this, we cannot get a true idea of the weight of an individual. For instance, if two persons have the same weight, 65 kilograms for example, and one of them has a stature of 1.85 metres and the other of 1.55 m.; it is evident that the first of these two will be very thin, because his weight is insufficient, while the second, on the contrary, will have an excessive weight.

A stout, robust child will weigh less, in an absolute sense, than an adult man who is extremely thin and emaciated; but relatively to the mass of his body, he will weigh more. Now this relative weight or index of weight, the ponderal index, gives us precisely this idea of relative embonpoint, of the more or less flourishing state of nutrition that any given individual is enjoying. Hence it is a relation of great physiological importance, especially when we are dealing with children.

The calculation of the ponderal index ought to be analogous to that of other indexes; what has to be found is its relation to the stature reduced to a scale of 100. In this case, however, we find ourselves facing a mathematical difficulty, because volumetric measurements are not comparable to linear measurements. Consequently it is necessary to reduce the measurement of weight by extracting its cube root, and to establish the following equation:

St:∛(W) = 100:X

whence

Pi = 100(∛(W))/S

The application of this formula necessitates a troublesomely complicated calculation, which it would be impracticable to work out in the case of a large number of subjects. But as it happens, tables of calculations in relation to the ponderal index already exist, thanks to the labours of Livi[35] and it remains only to consult them, as one would a table of logarithms, by finding the figure corresponding to the required stature, as indicated above in the horizontal line, and the weight as indicated in the vertical column.

Some authors have thought that they were greatly simplifying the relation between weight and stature by calculating the proportional weight of a single centimetre of stature and assuming that they had thus reduced the relation itself to a ratio based upon a single linear measurement (one centimetre), analogous to the ratio established by the reduction of the total stature to a scale of 100. But evidently such a calculation is based upon two fundamental errors, namely: first, no comparison is ever possible between a linear measure and a measure of volume; and secondly, the relation which we are trying to determine is that between synthetic measurements, i.e., measurements of the whole, and not of parts.

Fig. 37.

In the aforesaid method of computing (which is accepted by such weighty authorities as Godin and Niceforo), the number expressing the weight in grams is divided by the stature expressed in centimetres, and the quotient gives the average weight of one centimetre of stature expressed in grams. This method, which sounds plausible, may easily be proved to be fallacious, by the following illustration, given by Livi in his treatise already cited (Fig. 37). The two rectangles A and B represent longitudinal sections of two cylinders, which are supposed to represent respectively (in A) the body of a child so fat that he is as broad as he is long (the rectangle A is very nearly square), and (in B) that of a man of tall stature and so extremely thin that he very slightly surpasses the child in the dimensions of width and thickness (note the length and narrowness of rectangle B). Evidently the ponderal index of A is very high and that of B is very low. But if we calculate the proportional weight of one centimetre of stature, it will always be greater in the man than in the child, and consequently we obtain a relation contrary to that of the ponderal index.

Let us make still another counterproof by means of figures; let us take an adult with a stature of 1.70 metres and a weight of 19 kilograms; and a three-year-old child 0.90 m. tall and weighing 55 kg. (the normal weight of a child of four). In the case of the adult one centimetre of stature will weigh 65000/170 grams = 382 grams; while one centimetre of the child's height will weigh 15000/90 = 166 grams. In other words, one average centimetre of the child's stature weighs less than one centimetre of the adult, as it naturally should, while the ponderal index on the contrary is 23.6 in the case of the adult, and 27.4 in that of the child.

The reciprocal relations between stature and weight vary from year to year. In babyhood, the child is so plump that the fat forms the familiar dimpled "chubbiness," and Bichat's adipose "fat-pads" give the characteristic rotundity to the childish face; while the adult is much more slender. A new-born syphilitic child which, with a normal length of 50 centimetres, weighed only two kg.—and consequently would be extremely thin—would have the same identical ponderal index as an adult who, with a stature of 1.65 m., weighed 100 kg.

The evolution of the ponderal index forms a very essential part in the transformations of growth; and it shows interesting characteristics in relation to the different epochs in the life of the individual.

In this connection, Livi gives the following figures, for males and for females; from which it appears that at some periods of life we are stouter, and at others more slender; and that men and women do not have the same proportional relation between mass and stature.

It may be said in general, so far as regards the age, that the following is the established law of individual evolution: during the first year the ponderal index increases, after which it diminishes up to the period immediately preceding puberty (eleventh year for males, tenth year for females), the period at which boys and girls are exceedingly slender. After this, throughout the entire period of puberty, the ponderal index seems to remain remarkably constant, oscillating around a fixed figure. At the close of this period (seventeenth year for males, fourteenth for females), the ponderal index resumes its upward course (corresponding to the period in which the transverse dimensions of the skeleton increase, and in which the individual, as the phrase goes, fills out), and it continues to rise well into mature life (the individual takes on flesh); until in old age, the ponderal index begins to fall again (the soft tissues shrink, the cartilages ossify, the whole person is shrunken and wasted.)

Fig. 38.

Women, during their younger years are on a par with men in respect to the ponderal index, but in later life surpass them, because of woman's greater tendency toward embonpoint, since she is naturally stouter and plumper than man, who is correspondingly leaner and more wiry.

The following diagram indicates the progressive evolution and involution of the ponderal index throughout the successive stages of life:

The ponderal index has revealed certain physiological conditions in pupils that are extremely interesting. Some authors had already noted that the ponderal index was higher in well-nourished children (Binet, Niceforo, Montessori); but last year one of my own students, Signorina Massa, in a noteworthy study of children, all taken from the same social class and quite poor, and who did not attend the school refectory or have the advantage of any other physiological assistance, established the fact that the more studious children, the prize winners, have a lower ponderal index and a muscular force inferior to that of the non-studious (negligent) pupils. That the development of the ponderal index stands in some relation to the muscular force, might already have been deduced from the fact that the greatest increase of weight is due, in the evolution of the individual, to the system of striped muscles. Studious children, accordingly, are sufferers from denutrition through cerebral consumption; furthermore, they are weakened throughout their whole organism; in fact, I discovered, in the course of researches made among the pupils in the elementary schools of Rome, that the studious children, those who received prizes, had a scantier chest measurement than the non-studious. This goes to prove that school prizes are given at the cost of a useless holocaust of the physiological forces of the younger generations!

That the ponderal index has an eminently physiological significance, is further shown by the following comparative figures between normal and weak-minded children. The stature, which is biologically significant, is lower in the weak-minded; but their ponderal index is greater when they are well fed, as in the asylums in Paris.

Accordingly, the sole cause of the physical inferiority of studious children is study, cerebral fatigue.

BIO-PHYSIOLOGICAL DIFFERENCES BETWEEN NORMAL AND WEAK-MINDED CHILDREN
(Simon and Montessori: Based on Children from 9 to 11)

It should be noted that in the foregoing table the normal children include both the studious and the non-studious.

CHAPTER II
CRANIOLOGY

Having finished the study of general biological questions and of the body considered in its entirety, we may now pass on to analyse its separate parts, treating in connection with each of such parts the social and pedagogic questions which may pertain to it.

The parts of the body which we shall take under consideration are: the head, the thorax, the pelvis and the limbs.

The Head.—When we pass from the body as a whole to a more particularised study of the separate parts, it is proper to begin with the head because it is the most important part of the whole body. The older anthropology, and biological and criminal anthropology as well were very largely built up from a study of the head; a study so vast and important that it has come to constitute a separate branch of science: craniology.

The fact is that the characteristics manifested by the cranium are chiefly in the nature of mutations rather than variations, and consequently the anthropological data relating to the cranium correspond more directly to the characteristics of the species, or in the case of man, to the characteristics of race. Hence they are of special interest to the general study of anthropology. But when these imitative characteristics, which are naturally constant and have a purely biological origin, undergo alterations, they are to be explained, not as variations, but as pathological deviations; and for this reason criminal anthropology has drawn a very large part of its means of diagnosis of anomalies and of degeneration from malformations of the cranium.

Furthermore, the cranium together with the vertebral column represents not only the characteristics of species, but also those of the genus; in fact, it corresponds to the cerebro-spinal axis, which is the least variable part of the body throughout the whole series of vertebrates; just as, on the contrary, the limbs represent the most variable part. Indeed, if we study separately the cranio-vertebral system and the limbs, through the whole series of vertebrates, we shall discover gradual alterations in the former, and sudden wide alterations in the latter. The cerebro-spinal axis (and hence the cranio-vertebral system) shows from species to species certain progressive differences that suggest the idea of a gradual sequence of modifications (from the amphioxus to man) to which we could apply the principle, Natura non facit saltus: while the limbs on the contrary, even though they preserve certain obvious analogies to the fundamental anatomic formation of the skeleton, undergo profound modifications—being reduced in certain reptiles to mere rudimentary organs, developing into the wing of the bird, the flying membrane of the bat, and the hand of man.

Since it is not only a characteristic of species and race, but of genus as well, the cranium constitutes one of the most constant anatomical features. For the same reason it is less subject to variations due to environment, and from this point of view offers slight interest to pedagogic anthropology. But since the cranium contains the organ on which the psychic manifestations depend, we have a deep interest in knowing its human characteristics, its phases of development, and its normal limits.

Head and Cranium

The term Head is applied to the living man; the Cranium, from which this branch of science takes its name, is the skeleton of the head. The cranium is composed of two parts, which may be virtually separated, in the lateral projection, by a straight line passing through the external orbital apophysis and extending to the auricular foramen, thus separating the facial from the cerebral portion of the cranium. Hence the cranium is the skeleton of the head in its entirety, and is divisible into the cerebral cranium and the facial cranium.

The Cranium.—The cranium is a complex union of a number of flat, curved bones united together by means of certain very complicated arborescent sutures, and forming a hollow osseous cavity of rounded form. I will briefly indicate the bones which form its external contour. On the anterior part is the frontal bone, terminated by the suture which unites it to the two parietal bones: the coronal suture; while the two parietal bones are joined together by the median or sagittal suture, which forms a sort of T with the other suture.

On the posterior side is the occipital bone, which is also joined to the two parietal bones, by means of the occipital or lambdoidal suture. Below the two parietal bones, in a lateral direction, are the two temporal bones; and between the temporal and parietal bones are situated the great wings of the sphenoid. The main body of the sphenoid is at the base of the cranium. Besides these there is another, internal bone, the ethmoid.

The Face.—The skeleton of the face is composed of fourteen bones; some of these are external and lend themselves to measurement; others which are internal and hidden contribute to the completion of the delicate scaffolding of this most important portion of the skeleton. The principal bones of the face are: the two zygomatic bones (articulating with the temporal, frontal and maxillary bones); the two nasal bones (articulating with the frontal and with the ascending branch of the maxillary, and uniting above to form the bridge of the nose; this is a bone of great importance in anthropology, because it determines the naso-frontal angle and the formation of the nose); the two upper maxillary bones, or upper jaw (articulating together in front to form the subnasal region; laterally with the zygomatic bones; above with the nasal bones; internally with each other, to form the palate, and posteriorly with the palatine bones); the mandible or lower jaw (a single bone, and the only movable bone in the cranium), articulating with the temporal bones by means of a condyle, and the separate parts of which are distinguished as the body of the mandible and the ascendant branches, which are united to the cranium.

Fig. 39.—Note the line of division between the cerebral and facial cranium; in addition to this the sutures are shown which divide the frontal, parietal, occipital and temporal bones. PD. Coronal Suture; DL. Sagittal Suture; AL. Lambdoidal Suture.

The bones of lesser importance, which are interior and hidden are: the two lacrymal bones (situated at the inner angle of the orbitary cavity), the vomer or osseous septum of the nose; the two bones in the nose which lie on each side of the vomer and are known as the turbinated bones (concha nasalis); and the two palate bones (which form the backward continuation of the palatine vault constituted by the maxillary bones).

Human Cranium and Animal Cranium.—The dividing line between the cerebral and facial cranium is of great importance in anthropology, because the relative proportions between these two parts of the cranium form a human characteristic, contrasting widely with the animal characteristics; and they offer a simple criterion for determining the higher or lower type of the human cranium. (Compare in this connection Fig. 40, skulls of the higher mammals and of man.)

Fig. 40.

The illustration represents a number of different animal skulls; and at the top are two human skulls, the one of an Australian and the other of a European. It will be seen that the proportions between the facial and cerebral portions are very different; in the animals, even in the higher orders such as the primates (orang-utan, gorilla, etc.), the facial and masticatory parts predominate over the cerebral.

One might even say that the skeleton gives us at a glance the characteristic psychological difference; the animal eats, man thinks; that is, the animal is destined only to vegetate, to feed itself; man is an entirely different species; he has a very different task before him; he is the creative being, who, through thought and labour, is destined to subjugate and transform the world.

There are still other characteristic differences between the animal and the human skull. The cerebral cranium of the ape is not only smaller but it is furnished with strong bony ridges, to serve as points of attachment for powerful muscles intended to protect the cranial cavity. The human skull is completely devoid of such ridges; it is perfectly smooth, with delicate contours; it might be described as "frail and naked"; for the word nakedness precisely expresses the absence of those defences with which the cranium of the anthropoid ape is so abundantly provided. Accordingly, the human cranium is undefended by soft tissues; and even the bony walls themselves are far from thick. If we take a transverse section of the bones of the cranium, we find that they are formed of two very thin layers of bone united by a porous, osseous substance; the external layer is in direct contact with the muscles of the scalp, and the internal layer with the brain. These two layers differ widely in their degree of elasticity: the external layer is so elastic that if it receives a bruising blow (provided this is not so heavy as to surpass its limits of elasticity) it will yield even to the point of touching the inner layer and then spring back to its original position without leaving any perceptible trace of the blow received (this is especially true in the case of infants),[36] while the inner layer is so unelastic as to appear almost as brittle as glass: so much so, for example, that the indirect shock of the same contusion may cause it to splinter into fragments, which may either penetrate the substance of the brain, or produce hemorrhages, or inflammatory reactions in the meninges—and sometimes may constitute the sole cause of epilepsy, and various forms of inflammation of the brain (even resulting in idiocy), and sometimes of meningitis and death.

Contusions on the heads of children, and in general blows resulting from falls or other causes, must be taken into serious consideration, in the history of the individual, even though they have left no profound traces externally.

This human characteristic of nakedness, of the absence of powerful bodily defences, is not limited to the head alone, but is diffused over the entire morphological organism. Man, considered as an animal, is weak; he is born naked and he remains naked, and destitute of those natural defences which explain the endurance and the survival of other species; neither the fur nor the plumage of mammals and of birds nor the bony shields of reptiles and scales of fishes serve as defences for this vertebrate, who has raised himself to the highest eminence in the zoological scale; neither the muscular strength and powerful teeth of the felines, nor the talons of the birds of prey have been his arms of conquest.

Nevertheless, man who has conquered the earth and overcome all his powerful biological enemies, owes his survival, equally with all other living creatures, to his victory over other animals and over his environment. Wherein lies the special strength of this little, feeble being, who has become the lord of the earth? It lies in his brain. The arms of this conqueror are wholly psychic. It is his intelligence which has prevailed over the might of other animals and enabled him to acquire the means of adapting himself to his environment, or else of adapting his environment to himself. His intelligence, which sufficed him as a weapon with which to achieve victory in the struggle for existence, is also the means which still permits him to continue on the road toward self-perfectionment.

The morphological importance attached by anthropologists to the cerebral cranium depends precisely upon this: that it is the envelope of the brain. If we examine the interior of the human cerebral cranium, we find that it has adapted its bony contours so faithfully to those of the soft tissues that it bears the imprint of the various parts of the brain (cerebrum, cerebellum), the convolutions, and even the blood-vessels of the meninges. Accordingly, a study of the cerebral cranium amounts to an indirect study of the brain itself.

Characteristics of the Human Cranium.—The characteristics of the human cranium are all associated with the great development of the volume of the brain. Let us assume that we have an elastic vessel, representing in form an animal cranium, open at the base through an orifice corresponding to the occipital foramen. If we inflate this vessel, it will not only begin to enlarge at the expense Of its folds (ridges), and to stretch and distend its walls (thinness and fragility of the cranial bones); but furthermore it will undergo a change in form, acquiring a more pronounced rotundity and pushing upward in its anterior part above the face. This part, rising erect above the face, and determined by the volume of the brain, is the forehead. Animals do not have an erect forehead; their orbits continue backward in an almost horizontal line, giving them an extremely receding brow. Corresponding to this preponderance of the cerebral portion, the facial portion retires below the brow, the mandibles do not extend beyond the anterior axis of the brain, and are so far diminished in volume that they assume, as compared with animals, a new function; in short, the mouth is no longer merely the organ of mastication, but also the organ of speech; its animal part has been spiritualised.

The Evolution of the Forehead.—Inferior Skull Caps; the Skull of the Pithecanthropus; the Skull of the Neanderthal Man. The forehead is so distinctly a human characteristic that mankind has not needed the help of anthropology in order to realise its importance—and as a sign of superiority, nobility or sovereignty, has placed upon the forehead the crown of laurel, or the crown of nobility or kingship.

Has the forehead always been a human characteristic, or have we acquired it little by little? Such a problem is associated with the evolution of the brain. There are in existence certain remains of the skeletons of primitive men, which show them to have possessed a cerebral cranium inferior in volume to that now attained by the human species; and in these remains the forehead is also profoundly different from that of to-day, in that it is much lower and slants backward, while the supraorbital arches are very prominent. Such is the evidence of the "cranial caps," discovered in the early geological strata.

In the tertiary strata of the island of Java, which in that remote epoch of the earth's history must, together with Sumatra, have formed part of the continent of Asia, which is considered as the "laboratory of races," a skull was found by Dubois which raised the problem whether it should be classed as that of an ape superior to those now existing, or of a primitive man. Prior to this discovery, it had been maintained that man did not make his appearance until the quaternary period. This supposed primitive man was called by his discoverer the Pithecanthropus, pithecanthropus erectus.

Remains that are unquestionably human occur in the quaternary period, in which however skeletons are very rare, as compared with relics of human labour or social life, relics which are found scattered everywhere throughout Asia and Europe as well (chipped flints). The various remains of skeletons show us skulls much inferior to those of modern man, but superior to that of the pithecanthropus. In treatises of general anthropology reproductions are given of human crania known as the Spy or Neanderthal type, belonging to the epoch when the gigantic mammoth still roamed the earth. The forehead is very low and receding and the orbital arches are enormously developed; while the cerebral capacity calculated from the cranial dimensions is inferior to that of modern man.

Consequently, as the brain increases in volume in the course of the revolution of the race, the cranium not only shows a corresponding volumetric increase, but at the same time alters its form, thus producing the forehead which little by little rises from a receding to an erect position, and becomes high where it was formerly low, while at the same time the prominent orbital arches disappear. Accordingly, we may consider the forehead as the skeletal index of the cerebral volume, and hence of the relative anthropological and intellectual superiority.

In addition to its above-mentioned value, it also furnishes us with a biological principle of much importance: the relation between the volume and form of the cranium.

While the volume has a significance that is relative to the mass of the body, the significance of the form is absolute.

Let us examine these two skulls: normal human skulls of our own epoch; one of the Celtic race (Fig. 46) and the other Sardinian (Fig. 43); that of the Celtic race is much larger and rounder; that of the Sardinian is very much smaller and more elongated.

If we were considering only the volume, we might say that it was simply a case of a microcephalic and a macrocephalic: two terms (microcephaly and macrocephaly) that fall within the province of pathology. On the contrary, these two skulls are normal, but they belonged to individuals characterized by differences of race; the one (small skull) having a low stature; the other (large skull) having a tall stature.

The volume of the head therefore bears a relation to that of the body; the volume has a relative significance. But the form in both of them reveals a state of normality; the two skulls have a high and erect forehead, and exhibit in their whole contour a fine and regular development. Therefore the form has an absolute significance. It even proves to us the normality of the volume, a fact which could not be determined by the volume alone.

Another mechanical correspondence between volume and form is disclosed when we compare the skull of a new-born child with that of an adult. The skull of the new-born child is much smaller in volume; but the form shows the relatively enormous volumetric development of the brain; in fact the skull is protuberant and the forehead bulges forward above the face (front bombé), while corresponding to this index of cerebral development is the enormous preponderance of the cerebral cranium over the facial cranium, which is so small as to be almost reduced to a simple rudiment.

Hence the form by itself alone reveals the infantile character of the cerebral volume, which, in relation to the bulk of the body is of far greater dimensions than in the adult. In fact, if a child simply increased in volume and its growth was not the sum total of a morphological evolution, the adult man would become a monster; his macrocephaly would be so exaggerated that his neck could not sustain the weight of the head (If the relations between the proportions in infancy were maintained through life the adult man would have a head with a perimeter of 130 centimetres, = 4 ft. 3 in.).

Aside from its mechanical relations to the volume, the form has characteristics dependent upon biological factors, such as the sex and the race. The female cranium in fact has a straighter forehead than the male and the orbital arches are absolutely wanting, while the entire surface of the cranium is smoother and more rounded.

Similarly, the different races exhibit forms determined by biological factors and not by mechanical causes—for instance, the degree of dolichocephaly (elongated cranium) and of brachycephaly (short cranium).

Hence the form is life's manifestation not only of the characteristics proper to the species, but also of the mechanical adaptations demanded by the material composing the body.

It may be said that the volume and the form of the cranium are dependent upon two different biological potentialities: the volume is mainly determined by the cerebral mass; the form, on the contrary, is mainly determined by the bony structure—no matter how completely form and volume coincide in their reciprocal mechanical relations.

That is, the attainment of a given volume of head depends upon the development of the brain; the bone follows this development passively, is the index of it, the skeletal representation of it, but never the determining factor.

At one time it was thought, on the contrary, that a precocious ossification of the cranial cavity would arrest the development of the brain; microcephaly was believed to be caused by a precocious closing of the sutures of the cranial bones; and there was a certain period when the surgical treatment of microcephaly consisted in the removal of a portion of the cranial bone, in order to allow the brain to develop freely.

Fig. 41. Fig. 42. Dividing line in human skull, as compared with that of gorilla.

Fig. 43.—Rounded ellipsoidal cranium.

Fig. 44.—Brachycephalic cranium (vertical norm)

Fig. 45.—Remains of spy cranium.

Fig. 46.—Brachycephalic cranium.

Fig. 47.—Egyptian cranium, 21st dynasty, ovoid type.

Fig. 48.—Dolichocephalic cranium, from lateral norm.

But the failure of such attempts afforded additional proof of the fact that the volumetric development of the cranium depends upon the brain alone.

If a precocious or abnormal suture occurs in the cranial bones, there does not follow an arrest of development, but simply a malformation; which is precisely in proportion to the potentiality of the brain, which grows less where the suture has been formed, and in compensation grows more than normally where the conditions of the bones permit of cerebral expansion; and a deformity results. Microcephaly on the contrary shows inferiority of form (smallness, receding forehead, etc.), but not malformation.

Anomaly of form, therefore, results only from anomaly of skeletal development, and is frequently found in conjunction with a normal development of the brain.

Consequently malformations of the cranium do not have the grave significance of biological inferiority or of degeneration that they were at one time believed to have; but frequently they must be considered in connection with pathological conditions resulting for the most part in delayed development in the embryo or in early infancy, producing a thickening of the bone, or a partial suturation of the points, or parts, or of the entire suture (punctiform synostosis, partial or total); sometimes the sutures remain unaltered, and the deformation must be attributed to various disturbances connected with the nutrition of the skeleton in the course of intrauterine evolution (hereditary syphilis, denutrition of the mother during pregnancy, etc.). In short, a cranium that is abnormal in form is an indication of pathological occurrences or of physiological errors that have resulted in altering the normal growth of the individual.

There are many anomalies in the form of the cranium, but here we will cite only the two principal ones, because they are the most frequent and most likely to be encountered in individuals whose growth has been retarded (from lack of nutrition) and consequently constitute signs of physiological inferiority often associated with social caste. These two forms are: scaphocephaly and plagiocephaly.

The scaphocephalic cranium (Figs. 51, 52), is characterised by being very narrow and flattened laterally; while the forehead and the occiput project in front and behind, the two parietal bones meet above almost in an angle, so that, if it were turned upside down, the vault of the cranium would have the appearance of the hull of a ship.

The plagiocephalic cranium is a cranium which is unsymmetrical in respect to its longitudinal axis; that is, it is not equally developed on the right and on the left.

As a matter of fact, our bilateral symmetry is an ideal standard rather than an absolutely attainable reality; we are all of us a little larger on one side and a little smaller on the other, but to so slight a degree as to escape superficial observation, so that in general we have apparently a bilateral symmetry—that is, we appear to be symmetrical according to the testimony of our senses; but a more delicate examination proves that this is not true. Plagiocephaly therefore represents an exaggerated case of a normal fact. Plagiocephaly may be simple or compound; it is simple when the asymmetry is partial; namely, when it is confined to the anterior or posterior portion; it is compound when it is total; and in such case we find a complete diagonal correspondence: for instance, if the right nodule in the frontal region is more prominent, the left nodule is more prominent in the left occipital region, or vice versa. In general it may be said that the various forms of plagiocephaly are produced by asymmetry of the nodules or of the flattened surfaces of the cranium. Even in the case of microcephaly and of macrocephaly, which are substantially anomalies of volume, we find corresponding characteristic abnormalities of form. The microcephalic cranium is of inferior type, suggesting that of the ape—in other words, it is a cranium which has mechanically adapted itself to a brain of inferior volume: the macrocephalic cranium, especially if the abnormality is due to rickets or to hydrocephaly, calls to mind the infantile type of cranium; it has the characteristic bulging forehead, while mechanical adaptation frequently renders it very round (pathological brachycephaly). We will take up this question again when we come to speak in particular of malformations and to describe the technical methods of cranioscopy. What more particularly concerns us now is a consideration of the normal form of the cranium and its morphological evolution.

Fig. 49.—Cranium of new-born child (lateral norm).

Fig. 50.—Cranium of new-born child (vertical norm).

Fig. 51. Fig. 52.

Scaphocephalic cranium.

Fig. 53.—Cranium of new-born child seen from above, showing polyhedric contour due to nodules of ossification; fontanelle of the bregma; and suture dividing the two frontal bones.

Fig. 54.—Ellipsoides (classified by Sergi).

The Morphological Evolution of the Cranium through the Different Periods of Life. Embryogeny. Order of Appearance of the Points of Ossification and of Synostosis of the Sutures.—In its successive transitions through the different periods of life, the cranium not only acquires successively greater volume, but it assumes forms corresponding to the different grades of morphological evolution. We may group its transformation under five different periods: 1. from conception until birth (embryonic evolution); 2. from birth until the end of the third year (infantile evolution); 3. from three years old until twenty (youthful evolution); 4. from twenty to forty (adult age); 5. from forty to the end of life (involution).

First Period.—In the earliest stages of intrauterine life the cranium consists of a membranous skin, enclosing the primitive cells of nerve tissue constituting the brain; it has a cartilaginous basal part, destined later to form the base of the skull (basioccipital and basisphenoid bones). But all the rest (the vault or cap of the cranium) remains in a membranous state, so that at this period the head of the embryo has not yet acquired a definite form.

Fig. 55.—Cranium of new-born child. Showing nodules and fontanelles.

In the second month of intrauterine life the phenomena of ossification have already begun to take place; that is, a fine network has formed, spreading over almost the entire surface, which proceeds to fill up its interstices with calcareous salts. This process, however, is more rapid and more intense at certain points (points of ossification), from which it cannot properly be said that the ossification radiates, but rather that at these points the general process is intensified and concentrated. There are five principal points of ossification: two frontal, two parietal and one occipital, which appear clearly defined and projecting like nodules, imparting to the cranium, when seen from above, a pentagonal form, which is the normal form of the infant cranium.

Second Period.—At birth the cranium has not yet completed the process of ossification, nor are the normal number of bones that will eventually compose the adult cranium, as yet definitely determined. Therefore the cranium of the new-born child has three distinct characteristics:

1. It is not yet uniformly rounded, but polyhedral because of the noticeable prominence of the five primitive nodules or centres of ossification (2 frontal, 2 parietal, 1 occipital, Figs. 53, 55).
2. Since the process of ossification of the bones is not yet completed, certain membranous portions or cranial fontanelles still remain, which are especially wide at the points where several bones meet. The principal fontanelle is that of the bregma (at the juncture of the two frontal with the two parietal bones, quadrangular). Next comes that of the lambda, which is much smaller (juncture of the two parietal bones with the occipital, triangular), and lastly the fontanelles of the asterion and the pterion, on opposite sides of the temporal bones, the former being situated behind and the latter in front.
3. Since the process of ossification is incomplete, the fusion of bony portions into entire bones, such as they are destined to be when complete development is reached, has not yet been accomplished; that is to say, certain bones of the cranium are still divided into several portions. For example, the frontal bone in the new-born child is composed of two bones, separated by a longitudinal suture that is destined to disappear, and the occipital bone is composed of four parts, namely, the base, the squama and the two condyles (basioccipital, exoccipital and superoccipital bones).

During the first period of three years, while the brain is increasing notably and rapidly in volume, the cranium undergoes various and interesting transformations. The pentagonal form of the cranium tends steadily to become rounder, because the primitive nodules are diminishing, or even disappear, although in this regard many individual varieties result; and the processes of ossification reach their completion. This is the most important period of growth, during which the individual development of the perfect cranial form may be attained, provided the rhythm of growth between the brain and its envelope remains harmonious; or again, certain deformations may be definitely established, owing to the intervention of some pathological condition or a disturbance of nutrition, altering either the internal volume or the normal process of ossification of the bony covering.

The first closing of the fontanelles takes place, in our race, in those of the asterion (posterior to the temporal bones), and next in those of the pterion; and it sometimes happens, as an anomaly of growth that leaves no external trace in the living man, that a little bone is formed, duplicating the shape of the fontanelle itself; such little bones, very common in abnormal crania, are called Wormian bones. They may occur in connection with any of the fontanelles, but especially with that of the bregma.

Fig. 56.—Cranium of adult with abnormal medio-frontal suture.

The fontanelle of the lambda generally closes during the first year; and the last of all the fontanelles to close is the largest, which is situated toward the front of the head, at the bregma, and is well known, even by the common people, and can easily be felt upon a child's head; it generally closes toward the end of the second year; and its characteristics may furnish valuable indications of abnormality or insufficiency of the child's development. For example, if it diminishes and disappears ahead of time, this may constitute the first symptom of microcephaly, or at all events, of submicrocephaly (i.e., a case of microcephaly that is not very pronounced). On the contrary, when this fontanelle remains dilated and delays its normal closing, this is a sign of organic weakness and debilitating disease (cachexia, rickets, myxedema). Furthermore, the fontanelle in question may alter its characteristic appearance in certain forms of sickness. In the case of hydrocephaly it becomes distended, while in enteritis, on the contrary, in which the organism parts with a large proportion of liquid, it becomes depressed.

The sutures also undergo notable changes during this period of life. The first to become effaced is the metopic or medio-frontal suture, which is destined to close and form a single bone; by the end of the first year it is obliterated throughout the middle third of its length, and thereafter the process of suturation spreads upward and downward until it is completed at the end of the second year (Welcker, Haeckel, Humphry). Sometimes, however, this suture is not obliterated until very late, and there are anomalous cases where it has remained throughout life, giving the forehead a characteristic form (pronounced frontal nodules and a slight palpable furrow along the medial line of the forehead).

During this same time a fusion has also taken place between the occipital squama and the two lateral or condyloid portions; but the resultant whole still remains separated from the corpus or base of the occipital bone, which will not become welded into one solid piece with the rest before the age of seven years.

At the age of three, the ossification of the cranial vault has been completed. In place of being depressed and protuberant, as it was at birth, the cranium has grown upward and forward in the frontal region, assuming an almost definitive form; the volume of the cranium has at the same time undergone an exceedingly rapid growth, attaining proportions very near to those of an adult.

From the age of three onward the head grows slowly, and its transformations are much slighter and fewer. The cranial capacity which at birth is 415 cubic centimetres, becomes at the age of three, 1,200, at the age of fifteen, 1,393, and in the adult, 1,400 cu. cm. respectively. Accordingly we might say that at the age of three a sort of repose has been established in the growth both of the the brain and of the cranium; this is the age at which an awakening begins in the child of that intelligence which is to put him in touch with the external world, and it is also the age at which he may begin his education in school.

Third Period.—There follows a slow and parallel growth of both brain and cranium. The ossification of the cranium itself reaches completion. At the age of seven the occipital is definitely solidified into a single bone and between the years of fifteen and twenty the body of the sphenoid also becomes welded to the occiput. This process of synostosis begins from the interior of the cranium, and only subsequently manifests itself externally. Consequently, the basilar suture closes at the time when the last large molars, the so-called "wisdom teeth," appear. After this period, the base of the cranium can no longer undergo any sort of growth, and in the case of uneducated persons the complete development of the cranium is definitely accomplished.

Fourth Period.—But in the case of cultured persons, those who form the class of brain-workers, the brain continues to grow, although extremely slowly, up to the age of thirty-five or even forty, thanks to the sutures which still remain completely intact and which still make an expansion of the bony envelope possible.

After this comes the beginning of the

Fifth Period.—The period of involution, during which the synostosis (closing) of all the cranial sutures will successively occur, until in advanced old age the cranium becomes composed of a single bone, just as in the embryo it was formed of a single membrane.

The synostoses which occurred in the early periods had an evolutive significance and were associated with the growth of the body and the intelligence. These later synostoses, on the contrary, have an involutive significance and are associated with the physiological decay of the organism and at the same time with that of the psychic activities.

The first point at which synostosis takes place is in the region of the obelion, that is, near the middle of the suture which, unites the two parietal bones; shortly afterward, the fronto-parietal sutures begin to unite along the pterion. At the age of forty-five, the obeliac synostosis has progressed as far as the lambda, and that of the fronto-parietal suture to the bregma; and at fifty the ossification is very nearly accomplished, at least on the right-hand side (according to Broca's series of crania). At seventy the squama of the temporal bone unites with the parietal, and at eighty the entire cranium has become a single bone.

These processes are subject to no small number of individual variations; there have been cases of persons who, although very old, still preserved many of their cranial sutures intact and their psychic activities remained correspondingly alert (men of genius). Conversely, the closing of the sutures sometimes begins as early as the thirty-fifth year. A diagnosis of age, as determined by the skeleton, is consequently only approximate.

During the periods of growth the cranium may exhibit transitory anomalies; it is very common to encounter in the heads of children of the lower social classes, who are consequently subject to denutrition, malformations which represent various degrees and forms of plagiocephaly, and which subsequently disappear completely, as the development of the cranium advances. Anomalies of form must therefore be judged differently in the case of the child than in that of the adult.

It may even happen that the five primitive nodules persist for a long time and even remain as a definitive form of the adult cranium constituting, according to Sergi, a distinct variety, the pentagonal cranium. But this is quite rare. From the frequency with which this form is to be observed in schools attended by children of the poorer classes, it is better to regard it as due to a delay in morphological evolution, which will probably disappear later on.

Normal Forms of the Cranium

We are indebted to Sergi for an exact knowledge of the normal forms of the cranium. Such forms are racial characteristics and are invariable, as Sergi has succeeded in proving by a comparison of the most ancient forms of the cranium with recent forms. Accordingly this authority takes the cranial formation as the basis for his classification of races. We have no direct interest, so far as concerns the special scope of our own science, in the value of this theory of classification—a theory, by the way, already divined, although very imperfectly and under a different form, by French and German anthropologists. Sergi's studies of cranial forms interest us solely as a diagnostic test of normality as compared with abnormality. For it is due to these researches that certain forms that used to be considered pathological, have come to be recognised as normal.

The normal forms of the cranium may be grouped, according to Sergi, under nine primary varieties, each of which includes sub-varieties.

These nine varieties are named as follows:

I. Ellipsoid; II. Ovoid; III. Pentagonoid; IV. Rhomboid; V. Beloid; VI. Cuboid; VII. Sphenoid; VIII. Spheroid; IX. Platycephalic.

Fig. 57.—Ellipsoides depressus cranium.

I. Ellipsoid (Fig. 58).—This form is recognised by inspecting the cranium according to the vertical norm (see in the chapter on Technique the method of cranioscopy).

The cranial contour recalls an ellipse in which no trace of the nodules remains, and in which the occiput is not in the least flattened; while the anterior half of the cranium closely corresponds to the posterior half.

The sub-varieties are differentiated by their greater breadth and length, by the form and protrusion of the occiput, and also by the height of the cranium measured vertically.

Fig. 58.—Ellipsoid cranium.

Fig. 59.—Ovoid cranium.

Accordingly, the sub-varieties have a binominal nomenclature indicating, in addition to the fundamental characteristic (variety) the qualitative characteristic of the sub-variety (e.g., ellipsoids depressus; compare Fig. 57, showing a cranium seen laterally).

II. Ovoid.—This form of cranium, seen from above, is that of an ovoid, with the broader portion corresponding to the parietal bones, at the point where the characteristic embryonal nodules are situated. The protrusions of the parietal bones are apparent (swellings) but not angular (nodules). The occiput protrudes and is broad (Fig. 59).

Fig. 60.—Pentagonoid cranium.

Fig. 61.—Rhomboid cranium.

III. Pentagonoid.—In this form, persistent traces of the five primitive embryonal nodules are still plainly visible, giving the contour of the cranium, when seen vertically, the appearance of a pentagon. The protuberances, however, are quite smooth and not pointed, as in the embryonal cranium.

Fig. 62.—Beloid cranium.

IV. Rhomboid.—This form is similar to the pentagonoid, excepting that the parietal breadth is much more notable in proportion to the forehead, which is much narrowed and has lost its nodules.

Fig. 63.—Ovoids (classified by Sergi).

Fig. 64.—Pentagonoides acutus (Sergi's collection).

Fig. 65.—Beloides lybicus (classified by Sergi).

Fig. 66.—Platycephalus orbicularis (classified by Sergi).

Fig. 67.—Platycephalus ovoidalis (classified by Sergi).

Fig. 68.—Spheroidal cranium, vertical norm (Sergi's collection).

V. Beloid.—The beloid, or arrow-head cranium is like the ovoid with the occiput more flattened, so that the widest portion is further back than in the ovoid; toward the front it becomes narrower, constituting altogether an admirably shaped type of head.

Fig. 69.—Cuboid cranium.

VI. Cuboid.—This form is most clearly perceived when the cranium is seen either sidewise or from the rear. Not only the face, but the lateral and occipital walls as well are flattened; so also is the forehead, which in general is quite vertical.

VII. Sphenoid (cuneiform).—The broadening between the two parietal bones is usually far back and very evident, while the cranium narrows toward the front. The occiput is flattened.

Fig. 70.—Sphenoid cranium.

VIII. Spheroid.—Seen vertically, it presents the appearance of a very broad ellipse; all the curves tend to become spherical. The forehead, however, is not notably vertical.

IX. Platycephalic.—The fundamental characteristic of this type of cranium is that it is flattened on top, or rather, since such flattening cannot be absolute, the arch of its vault is a segment of a circle of very large diameter (Sergi), with the result that this cranium has the appearance of being very low vertically and very broad laterally. When seen vertically it may present a wide variety of contours, ellipsoid, ovoid, pentagonoid, etc., but its distinguishing characteristic remains that of the flattened vault.

Fig. 71.—Spheroid cranium.

Sub-varieties.—Sphenoids trapezoids, or trapezoid cranium. Observed from the vertical norm, this form appears as a variety of the sphenoid; and when seen laterally it is characterised by the lines of its contour forming a trapezium. Starting from the vertex of the cranium one line slants toward the forehead and another toward the occiput, which is very massive. In the figure given below, the quadrangle drawn in solid lines serves to indicate the correct position of the cranium, while the trapezium formed of dotted lines gives us its characteristic form.

Fig. 72.—Trapezoid cranium.

Among the forms described by Sergi, are several which were formerly held to be abnormal, such, for instance, as the platycephalic cranium and the pentagonoid. Similarly, when the surfaces of the cranium showed a tendency toward flatness, or when there were cranial protuberances, even though these were destined to disappear, they were regarded as malformations. Before this high authority offered us his guidance, there were certain forms, frequently encountered, that it was difficult to define, for example, the trapezoid cranium, which often presents a notable vertico-occipital flattening, with the vertex notably higher than the forehead.

There are also certain forms of cranium having the frontal region more restricted than the parietal region, or slanting down from a much elevated vertex, which have been proved to be normal forms; while still another error previously made was that of trying to judge the forehead on the criterion of a single model, deviations from which were much too readily relegated to the category of abnormalities. The most regular and beautiful forms, and the ones that are commonest in our racial stocks are the ellipsoid, ovoid and sphenoid. In my work on the women of Latium, precisely one of the points that I noted was the frequent occurrence of certain sub-varieties of the ellipsoid and the sphenoid.

In order to recognise the forms of the cranium, a certain training is necessary which each one must acquire for himself. Observations of the cranium will make it easier to judge of the form in relation to the head, at least, when the latter is not too much hidden by the hair, as often happens in the case of young children.

A knowledge of the normal forms of the cranium will also guide us in our judgment of many abnormal forms, which very often present the appearance of exaggerations of normal types.

Thus, for example, the acrocephalic cranium (much raised in the parieto-lambdoideal region and sloping forward toward the brow, while the occipito-lambdoideal region is flattened) recalls the trapezoid; and the clinocephalic cranium (in which the coronal suture forms a slight girdle-like indenture and divides the contour of the cranium, when observed along the vertical norm, in two curves, a lesser anterior and a greater posterior curve, resembling a figure of 8) recalls certain varieties of ovoid cranium described by Sergi. This brings us to a principle that is very interesting to establish, namely, that frequently anomalies represent exaggerations of the racial or family type.

The Cephalic Index

Retzius was the first to take the cranium under consideration as a basis for a classification of the human races; and he attempted to determine a concept of its form by means of a numerical formula expressing the relation between the length and width of the cranium (cephalic index). Thus he distinguished the races into brachycephalics, or those having a short head; and dolichocephalics, or those having a long head. Following Retzius, who may be regarded as the founder of craniology, Broca adopted, completed and expanded this method, deriving from the cranium, or rather from the particular character given by the cephalic index, a key, as it were, suited to unlocking the intricate mysteries of hybridism among the human races. Consequently the cephalic index was not confined, as regards its importance, within the same limits as all the other indexes, but was raised by the French school, warmly seconded by Italian anthropologists, to the dignity of a fundamental determinant of the ethnic type, as definitely as, for example, the vertebral column serves as basis for a classification including all species of vertebrates.

The Germans refused to accept the cephalic index as determining the classification of races; but while seeking to prove themselves independent of it, they continued to regard the form of the cranium as a basis of classification (Rütimeyer, von Höller, and to-day Virchow), but without ever having identified, as Sergi has now done, existing forms as normal types of race.

The cephalic index is obtained by the well-known formula expressing the relation between the maximum transverse diameter of the skull (see "Technique") and the maximum longitudinal diameter reduced to 100, and is expressed as follows: Ci = 100×d/D (the cephalic index is equal to a hundred times the lesser diameter divided by the greater; in the present case the lesser diameter is the transverse).

This proportion between linear measurements cannot properly sum up the form of the cranium. We can, for example, conceive of a microcephalic cranium having a normal cephalic index, since the relation between the two maximum diameters necessary for deducing the index, does not tell us, for example, either the dimension of the cranium or the form of the forehead.

If, for instance, we should imagine a photograph of a cranium enlarged a hundred diameters, the reciprocal relations between the length and the width would still remain unchanged.

In order to demonstrate that the cephalic index does not determine the form of the cranium, Sergi makes use of a number of different geometric figures, such as a triangle, an ellipse, a trapezoid inscribed within equal rectangles, and which consequently have an equal base and equal altitude, that is, the same proportion between length and width.

It follows that skulls corresponding more or less closely in shape, trapezoidal, trigonocephalic, ellipsoidal, plagiocephalic, and hence both normal and abnormal, can be expressed by a cephalic index having the same identical figures.

But, although the cephalic index is far from being descriptive in regard to the form of the cranium, it constitutes an anthropological datum that has two advantages: 1. It depends upon measurements and is therefore accessible to those who, not being anthropologists, lack the trained eye that can distinguish with careful accuracy the true forms of the cranium in their manifold variety. Furthermore, since the measurement of maximum diameters is sure and easy and may be obtained with exactness, regardless of the thickness of the hair, it may be applied in anthropological research to all subjects. 2. The cephalic index, even if it does not give us the form, does give us a fact which has a bearing upon the form, namely, whether the cranium is long or short; in other words, it substantially represents the most real and evident difference between the different types of cranium. And since the cranium has a visibly spheroid form, that is, with smooth and rounding surfaces, and constantly adheres to this generic delineation, the fact of being longer or shorter introduces a definite differentiation into the general and accepted form, and gives a very simple and concise indication of it, that conveys the idea more clearly than a description would.

Granting the practicality of this line of research, the cephalic index may also be accepted as an index of form, so long as there is no intention of going deeply into minute differentiations for systematic purposes. Professor Sergi himself, author of the system that forms the basis of the study of cranial forms, urged me to exclude from a practical course in pedagogic anthropology the classification of forms, limiting the concept of form to that included in the cephalic index.

The cephalic index has the additional advantage of having been extensively studied and consequently of having an abundance of mean averages for comparison that are of great practical use. Furthermore, the idea it gives regarding the cranium by means of one simple figure serves to convey certain fundamental principles with great clearness.

In dealing with figures that determine an anthropological datum of such high importance, it is necessary to define its limits and its nomenclature.

Various authors have introduced their own personal classification of the cephalic index, and no small confusion in nomenclature has resulted; so much so that a need was felt of establishing a uniformity of numerical limits and of the relative terminology, in other words, of simplifying the scientific language.

Accordingly, a congress was held at Frankfort in 1885, at which the following nomenclature was established by international agreement:

• CEPHALIC INDEX.—Nomenclature established at Frankfort
• Dolichocephalia = 75 and below
• Mesaticephalia = from 75.1 to 79.9
• Brachycephalia = from 80 to 85
• Hyperbrachycephalia = 85.1 and above.

Previous to this, the most widely varied classifications were in use, and the leading authorities had all introduced into the literature of the subject their own personal classifications. Here are some of the more important:

It remains to determine the extreme limits of oscillation of the index, both in relation to the normal mean and in relation to the fluctuations of this important ethnic datum in a given population.

Topinard, as we have seen, gives as his mean figures for the extreme normal limits among the human races 64 and 90.

Deniker gives, as his mean averages for the human races, the following figures: For dolichocephaly, 69.4 (natives of the Caroline Islands; Australia); For brachycephaly, 88.7 (the Ayssori of the Transcaucasus; Asia).[37] But we know that a mean is obtained from figures either greater or smaller than the mean itself, so that the limits of individual variation must exceed that of the given figures.

Accordingly the oscillation of the normal cephalic indices may be given as ranging from 70 to 90.

In regard to abnormalities (extreme human limits of the cephalic index) the authorities give 58 for dolichocephaly (scaphocephaly) and 100 for brachycephaly (in which case the cranium is round and known as trochocephalic; it is met with among the insane).

Between oscillations of such extremely wide range in the normal cephalic index, the number chosen as a medial figure to serve the purpose of dividing the dolichocephalics from the brachycephalics is that of 80, which is included within the division of brachycephaly. In spite of the nomenclature established at Frankfort, there is a distinct scholastic advantage, because of the greater simplicity of memorising and fixing the idea, in reverting to the nomenclature of Retzius, who classes as brachycephalics all crania from 80 upward, and as dolichocephalics all those below 80. It is certainly strange to class all crania from 80 to 90 without distinction as brachycephalics, and then to alter the name and call a cranium with an index of 79.9 a dolichocephalic. It has been found that there is always a slight difference between the index taken from measurements of the cranium and that obtained from measurements of the head. According to Broca, it is necessary to subtract two units from the cephalic index taken from a living person, in order to obtain that of the cranium; thus, for example, if the cephalic index (taken from life) is 80, the cranial index (taken from the skeleton) would be 78. Such differences are due to the disposition of the soft tissues. Consequently, even according to the simple subdivision of Retzius, a person who was brachycephalic during life, would become dolichocephalic after he was dead.

But this is what always happens in biology, whenever we try to establish definite limits. Life undergoes an insensible transition through successive limits and forms, and this fact constitutes the grave difficulties and the apparent confusion of biological systems. In determining degrees of difference, it is necessary to have recourse constantly to special methods, which teach us to recognise general properties and to use them as a basis in dividing living creatures into separate groups (see in the section on Method, "Mean measurements and formation of series in relation to individual variations").

Hence, for mnemonic purposes, we need remember only the single number, 80.

But if we wish to adopt the nomenclature of Frankfort, it is necessary to keep in mind two figures denoting limits, 75 (inclusive) for dolichocephaly, and 80 (inclusive) for brachycephaly.

These constitute, as it were, two centres, beyond which, on this side and on that, we may picture to ourselves the individual variations drawn up in martial line. In this case, the space between 75 and 80, in other words, the limits of mesaticephaly, may be interpreted as due to oscillations between dolicho- and brachycephaly according to the laws of variability, which is analogous to what takes place in the case of oscillations in the opposite direction (70-75 dolichocephaly; 80-85 brachycephaly). From this point of view, these two numbers, 75 and 80, constitute median centres of two different types.

But according to Broca and his school—and this view is accepted by many anthropologists—mesaticephaly should be regarded as constituting a fusion of the two other types, the brachy- and dolichocephalic, whence it follows that mesaticephalics would be hybrids. Other authorities, on the contrary, exaggerating the conception of the fixity of the cephalic index in a given race, admit the existence of mesaticephalic races.

Fig. 73. Map of the Cephalic Index in Italy.

But it has been observed that the greater number of mesaticephalics are to be found in regions where dolichocephaly prevails; in certain districts of Africa, as for example, in Somaliland, not a single brachycephalic exists, yet none the less the mesaticephalics are numerous. Accordingly, mesaticephaly may be classed with dolichocephaly and regarded as one of its variations, while it seems to be independent of brachycephaly. Therefore the nomenclature of Retzius may for many good reasons be chosen and adopted in our schools. In conclusion, we shall regard the brachycephalics and dolichocephalics as the two fundamental types; and shall adopt the figure 80, included among the brachycephalics, as the limit of separation. The different grades of dolicho- or brachycephaly are to be determined by mean averages, and the oscillations due to individual variations, by series.

Hence it is important to determine the mean average and the oscillation of the cephalic index for the different races; and this is of interest to us as educators, in order to establish the limits of normality.

The practical method of studying the cephalic index is according to geographical distribution.

Here are a few general data of the cephalic index relative to its distribution:

The most dolichocephalic of all peoples are found in Melanesia, Australia, India and Africa. In the Fiji Islands the mean cephalic index is 67; in the Caroline Archipelago it is 69; in various regions of India, 71; that of the Hottentots, 74; of the Bantus, 73. Belonging to the dolichocephalics or mesaticephalics are the populations of the extreme south of Europe (Mediterranean race) and at the extreme north (English, Scotch). On the contrary, the races of western Europe and of central Asia are brachycephalic (Celts, Mongols). The most brachycephalic of all these peoples are met with in the Transcaucasus; their mean average is 88.7. There also exists a notable brachycephalic type in France (Savoyards, 86.9; inhabitants of the upper Loire, 87.4); also in Dalmatia, 80, while the Lapps of Scandinavia are also ultrabrachycephalic, 87.4.

On very general lines, it may be said that the dolichocephalics are the Eurafrican races (including the Mediterranean race, with which the first civilisations are associated: Egyptian, Greek and Roman) who migrated from the Mediterranean basin into Europe; and the brachycephalics are the Eurasian races, who on the contrary migrated from continental Asia across western Europe (the Aryans).

As far as regards Italy, its population is by no means evenly constituted. The median index given by Livi for Italy, deduced from observation of more than 29,000 subjects is 80; in regard to regional distribution, the results are shown in the following table:

Let us remember that if the cephalic index were measured directly from the cranium, the result would be one or two units less, hence the mean average of the cranial index would be about 78.

The accompanying map represents still more clearly the geographical distribution. The results show that in Piedmont, in Emilia, and in Northern Italy in general the inhabitants are more brachycephalic; while in the south and more especially in the island possessions we find the more dolichocephalic part of the population. The highest degree of dolichocephaly is found in Sardinia.

But if, instead of the cartographic summary herewith reproduced, we could examine the exhaustive one with which Livi has illustrated his great work on Anthropometry, we should discover that the distribution does not follow the great regional lines; but that as a matter of fact certain human groups exist, isolated like little islands, which have a cephalic index in marked contrast to that of the remaining population of the same region.

Thus, for example, at Lucca, in the midst of a brachycephalic population, there is a pronouncedly dolichocephalic group; and in the midst of the dolichocephalic population of Abruzzo and the neighbouring provinces, there exists at Chieti a strongly brachycephalic group. Besides these and similar groups contrasting with the regional type, there exist a multiplicity of differences, from one successive boundary line to another, so that the limits of the cephalic index may be determined with great minuteness in the various regions.

Livi's large charts lend themselves with great clearness to this sort of analytical study, which would be found to be very profitable to teachers.

It is also quite instructive to compare the different charts representing various anthropological data of ethnical importance; such, for example, as that of the distribution of stature and that of the distribution of pigmentation. These data are regarded by anthropologists as attributes of race. Well, in these three charts it is evident at the first glance that there is a notable resemblance in distribution, so much so than an eye untrained to observation would be likely to confuse them. The cephalic index, the stature, the colour of the skin are consequently of almost uniform distribution. Corresponding to the most pronounced brachycephaly, we have the tallest stature and the fairest complexion; corresponding to the most pronounced dolichocephaly, we find instead the lowest stature and the most brunette types. Such an accumulative coincidence, in certain communities, of characteristics, in contrast to those that are found combined in certain other communities, reveal the existence in Italy of two different races. One of these races seems to have descended from over the Alps; the other, to have landed on the shores of the Mediterranean. The first belong to the Eurasians; the second to the Eurafricans.

In my work upon the population of Latium, the mean cephalic index obtained by me is 78. The distribution according to the localities studied affords the mean averages noted in the following table, in which I have also recorded the maximums and minimums, and the percentage of brachycephalic and dolichocephalic individuals who contributed to the given means:

CEPHALIC INDEX AMONG THE PEOPLE OF LATIUM
(According To Montessori)

The results show a preponderance of brachycephalics or of dolichocephalics in the places where the mean cephalic index is respectively highest for brachycephaly (Orte) or for dolichocephaly (Castelli Romani). Furthermore, the extreme maximum and minimum figures are found to be included in these groups (90 at Orte and 70 at Castelli).

It should be noted that at Castelli Romani the mean average is mesaticephalic (76), notwithstanding the absence of brachycephalics; this average is based on figures showing an extremely pronounced dolichocephaly (ranging to 70!). The groups at Castelli and at Orte also showed characteristics in respect to stature (see page (111)); at Orte the mean stature is 1.61 m., with a maximum of 1.70 m. (very tall statures for women), and at Castelli the mean stature is 1.47 m., with a minimum of 1.42 m. (low statures).

Similarly, in regard to pigmentation, I found at Orte a prevalence of blonds, and at Castelli of brunettes. Hence the conclusion may be drawn that at Castelli and at Orte there exist groups of human beings who are of almost pure race, in the midst of a population in which racial types have become attenuated or hidden; but in centres like these we still find persistent testimony as to the ethnic factors that combined to form the people of Latium: the one, a blond, tall, brachycephalic race; the other, dark, small, and dolichocephalic.

The Cephalic Index at Different Ages of Life.—Another quality that renders the cephalic index of great importance is that it remains constant in the course of growth, since the two maximum diameters, the antero-posterior and the transverse, increase at very nearly the same rate, excepting during the earliest years, at which time the length of the cranium increases slightly more than the width. According to some authorities it is in the second year, according to others it is in the fourth or seventh, that the cephalic index becomes constant (Binet, Deniker, Pearson, Fawcette, Ammon, Johannson, and Westermarck).

The following table is one that I have drawn up on the basis of Quétélet's figures:

CEPHALIC INDEX