Skull of Ancient EgyptianFIG.12.—Skull of ancient Egyptian exhumed at Thebes,with principal craniometrical lines.
FIG.12.—Skull of ancient Egyptian exhumed at Thebes,with principal craniometrical lines.
But the parts that deserve particular attention are the orbits and the nasal skeleton. The orbital orifice represents a quadrilateral figure more or less irregular, more or less angular or rounded, the length and breadth of which canbe measured. According to Broca,[61]the breadth is measured from the point called dacrion (Fig.12,X) (situated at the intersection of the fronto-lachrymal suture and the crista lachrymalis) to the most distant point of the opposite edge of the orbit (Fig.12,Y); the height (Fig.12,T Z) is also measured perpendicularly to the preceding line. The relation of this height to the breadth = 100, or the orbital index, expresses in figures the form of the more or less shallow quadrilateral of the orbit. What are called average orbits, ormesosemes, are those whose index varies from 83 (Broca), or from 84 (Flower), to 89; shallow orbits, ormicrosemes, those which have the index lower than 83 or 84; finally, higher or large orbits,megasemes, those which have their index from 90 and upwards. The annexed table gives the orbital indices of the principal populations of the globe.
Profile ViewFIG.13.—Same skull as Fig.12, profile view.
FIG.13.—Same skull as Fig.12, profile view.
TABLE OF ORBITAL INDICES.(Crania of both Sexes together; series of more than 10 subjects.)
The capacity of the orbital cavity and its depth are also measured, but, as the researches of L. Weiss have demonstrated, there is no correlation between the form of the skull (dolicho- or brachy-cephalic) and this depth. On the other hand, it appears to have some relation with the form of the face; broad faces (chamæprosopes) have deeper orbits than long faces (leptoprosopes).[63]
The skeleton of the nose presents numerous variations according to race. The nasal bones may be more or less inclined, one in relation with another, so as to form either an almost flat plane or a sort of prominent roof; their outline may be straight, concave, or convex; their breadth and their length also vary. The form of these bones, together with the nasal opening which is found below, may be expressed by the figures of the nasal index—that is to say, of the relation between the height of the bony mass (from the root of the nose to the anterior nasal spine) and its breadth (linesV BandE Dof Fig.12). According to the greater or lesser breadth of the nasal bones and of the nasal opening, the skull is calledleptorhinian(long-nosed) orplatyrhinian(flat-nosed); the intermediate forms bear the name ofmesorhinian. The form of the nasal opening appears to be transmitted very tenaciously by heredity (Broca).
The following table, in which I have introduced only series of more than ten skulls, gives the distribution of the principal ethnic groups according to their nasal index.
It is easy to see in running the eye over this table, that almost all the populations of the so-called white races are leptorhinians, while all the yellow populations are comprised exclusively in the group of mesorhinians, and Negroes and Bushmen in that of the platyrhinians.
The Polynesians seem to be leptorhinians, the Melanesians with the Australians show a tendency towards platyrhiny.
NASAL INDEX OF THE CRANIUM.(Series of more than 10 Skulls of both Sexes together.)
Prognathism, that is to say the degree of projection of the maxillary portion of the face, is a characteristic trait of certain skulls; however, it does not seem to play so important a part in the classification of races as anthropologists had thought twenty or thirty years ago. It presents too many individual varieties to be taken as a distinctive character of race. The degree of prognathism is measured by means of differentfacial angles, of which that of Cloquet, passing by the forehead, the upper alveolar point (between the two incisors), and the external auditory meatus (Fig.13,F O K), is one of the best. However, as it expresses the relation of points too far removed from each other, it is better to confine ourselves to the measurement ofalveolar prognathism, that is to say, of the sub-nasal projection of the face. This prognathism is measured with the angle determined by the alveolar point, the external auditory meatus, and the nasal spine (Fig.13,F′ O K).
Jenny, Australian WomanFIG.14.—Jenny, Australian woman of Queensland.Height,1 m. 56; cephalic index, 71.2; nasal index, 119.(Photo. Prince Roland Bonaparte.)
FIG.14.—Jenny, Australian woman of Queensland.Height,1 m. 56; cephalic index, 71.2; nasal index, 119.(Photo. Prince Roland Bonaparte.)
Among numerous other measurements which give indications for certain characters we must cite: the minimum frontal diameter (Fig.12,S J); the interorbital line; the length and the breadth of the palate, the relation of which constitutes thepalatal index, etc. Among the measurements of the curves it is necessary to note the horizontal circumference of the head, the antero-posterior curve with its frontal, parietal, and occipital portions, etc. Besides the facial angles, a great number of others are taken; the more important are the sphenoidal angle and the different occipital angles (of Daubenton, Broca, etc.), which give the inclination of the occipital foramen in relation to a horizontal plane. The measurements of these angles furnish valuable indications on the characters calledseriary, to which we have recourse in order to compare man with animals which bear the closest resemblance to him.
Jenny, in ProfileFIG.15.—Same subject as Fig.14, seen in profile.Example of nose concave and flattened, of prognathism, and of prominent superciliary arches.(Photo. Prince Roland Bonaparte.)
FIG.15.—Same subject as Fig.14, seen in profile.Example of nose concave and flattened, of prognathism, and of prominent superciliary arches.(Photo. Prince Roland Bonaparte.)
But all these measurements do not suffice to exhaust the data of the morphology of the skull. There still remain a host ofdescriptivecharacters: the general form of the skull, pentagonal, oval, elliptical, etc.; the contour of the face more or less angular or rounded, itscanine fossamore or less deep, its zygomatic arches, and its molar bones more or less projecting, etc. Certain anomalies in the sutures of the bones, as for example the persistence of the medio-frontal suture, the dispositions of thepterion(point of union of the sutures between thefrontal, the temporal, the sphenoid, and the parietal bones), are only important as seriary characters, but there are others which possess some value in the differentiation of races. TheWormian bones, or points of ossification inserted between the bones of the skull, are of the number. One of these bones found between the parietal bones and the occipital, haseven received the name of theInca bone(Fig.23,A), on account of its very frequent occurrence among Peruvian crania (deformed or not). In fact, it is met with in an imperfect state 20 times in 100 and perfect 5.4 times in 100 among Peruvians, while in Negro crania it is found only 6 times in 100 imperfect, and 1.5 perfect; among Europeans it is still more rarelyimperfect, and is hardly ever met with perfect (Anuchin). This peculiarity seems to be a special character of the American race, seeing that among the crania of the Indians of the New World (outside Peruvians) the anomaly in question is found 10 times in 100 imperfect and 1.3 times perfect. Among the Indians of Rio Salado, an affluent of the Gila in Arizona, the frequency of this anomaly is still greater than among Peruvians (5.7 perfect cases against 5.4 in Peru).[64]In the same way, the presence of a suture which divides into two, more or less imperfectly, the malar bone (Fig.23,B) appears to be a special character of Ainu and Japanese crania; Hilgendorf has even proposed to call the lower portion of the malar bone thus formedos japonicum(Fig.23,B,a). While the suture is only met with 11 or 12 times in 100 in Mongolian races, and 9 times in 100 in European races according to Ten Kate,[65]it is found from 25 to 40 times in 100 among Japanese according to Doenitz.
It is well understood that in the description of crania the alterations of form produced by all kinds of causes are taken into account. (Such, for example, is the considerable asymmetry orplagiocephalydue to a physiological cause, as the hypertrophy of the capacity of the skull, or its atrophy in the pathological cases ofhydrocephalyormicrocephaly, and so many other ethnic deformations which will come up for treatment inChapter V., etc.)
The head of the living subjectfurnishes more numerous characters than the skull, especially if the face be considered with the play of feature. Sometimes an examination of the face suffices to determine the race of the subject.
The measurements of the head are about fifty in number, but they are not all of equal importance. Very few of them, indeed, are really useful.
The chief of theangular measurementsis the facial angle; great importance was formerly attached to it when prognathism, or the degree of projection of the maxillary region,was considered as a character of inferiority. In spite of the numerous instruments invented (double square, Harmand’s instrument, Jacquard’s goniometer, etc.), great precision in these measurements is not attainable. The only angle which can be taken with sufficient exactitude, thanks to the facial medium goniometer of Broca, is Cuvier’s angle, formed by a line running either from the glabella or the point between the eyebrows to the interval between the incisor teeth, and by another line starting from the external auditory meatus towards this interval. This angle enables us to estimate thetotal prognathismand thealveolar prognathism, but the variations which it presents are too slight (3 to 4 degrees), taking race with race, to constitute a distinctive character. Prognathism of the lips, pushed forward to form the prominence of the “muzzle,” which gives so characteristic an expression to the profile of certain Negroes or Australians (Fig.15), is not expressed by this measurement, and ordinarily cannot be measured in any way.
Among themeasurements of the curve of the headthe principal are those of thehorizontal circumferencewith itsanterior and posterior portions, the limits of which are found at the supra-auricular point, that is to say, in the depression which is found immediately in front of the spot where the helix of the pinna of the ear is inserted. The value of this measurement has also been exaggerated, it being said that men of well-developed minds have the circumference greater than men without intellectual culture. The comparative observations of Broca made on house-surgeons and attendants of hospitals seem to bear out the assertion; but they have not been confirmed, and stature appears to have a decided relation with the size of the head.
Japanese OfficerFIG.16.—Japanese officer (old style), born at Tokio.Example of elongated face.(Phot. Coll. Mus. Nat. Hist., Paris.)
FIG.16.—Japanese officer (old style), born at Tokio.Example of elongated face.(Phot. Coll. Mus. Nat. Hist., Paris.)
The measurements in a straight line are more numerous and more important than those of angles and curves. Those which give the antero-posterior diameter or maximum length of the head (from the glabella to the most prominent point of the occiput, as on the cranium) and the transverse maximum diameter, are the first to note. We have already seen (p.57)that their centesimal relation constitutes what is called thecephalic index. Let us note afterwards thetotal height of the head(projection on a vertical plane), themaximum breadth of the face(between the zygomatic arches) and the different “lengths” of the face, the relation of which to the breadth constitutes thefacial index. The latter is far from expressing the form of the face as well as does the cephalic index the form of the head, on account of its irregularity, and the want of agreement between anthropologists with regard to the “facial lengths.” Nevertheless we distinguish according to these measurements elongated faces orleptoprosopic(Fig.16),short faces orchamæprosopic(Fig.17), and medium faces,meso-orortho-prosopic(Fig.14).
Two Naga MenFIG.17.—Two men, Nagas of Manipur.Examples of large faces with prominent cheek-bones.(Phot. Miss Godden.)
FIG.17.—Two men, Nagas of Manipur.Examples of large faces with prominent cheek-bones.(Phot. Miss Godden.)
Other measurements taken are thefrontal minimum diameteror minimum breadth of the forehead (between the temporal ridges of the frontal bone, which makes a projection under the skin); thedistance between the inner anglesorcanthusof the eyes is a good measurement, especially if it be compared with thebreadth of the nose, taken by just touching with the points ofthe callipers the alæ of the nose. Referred to the length of the nose (between the root of the nose and the point of insertion of the septum) reduced to 100 it gives thenasal index, one of the important characters in the classification of races. Among several other measurements may be mentioned thebreadth of the mouthbetween the commissure of the lips, the subject being in repose; thelength and the breadth of the ears, etc. All these measurements are taken either with callipers or with sliding compasses, similar to those used by shoemakers or engineers, or with special instruments.[66]
Measurements taken on the living subject can never be as accurate as those obtained on the cranium; but, on the other hand, they may be much more numerous, and the greater number of observations compensates largely for individual errors due to difficulties of the mode of operation. Further, when measuring heads of living subjects, there is the advantage of knowing sex, approximate age, and exact origin, while in the case of one-half the crania examined, one or more of these particulars may be wanting. All these conditions sufficiently explain why, in these latter days, the attention of anthropologists is directed towards measurements of living subjects, among which those of the head occupy the foremost place.
Do the measurements of the head of the living subject correspond to the measurements of the cranium? Various researches made with the object of elucidating this question leave it still unsettled. It was believed at first, for instance, that thebregma, or point of junction between the coronal and the sagittal sutures in the cranium (Fig.11, O), corresponded in the head with the most prominent point of the line passing from the supra-auricular point to another perpendicularly to the horizontal plane; but the very careful researches of Broca and Ferré have shown that this point is always in front of the bregma by a quantity which varies according to sex and individual. The correspondence of thetourbillonof the hair with thelambda, or point of junction on the cranium of the sagittal and occipital sutures (Fig.11,F), has not either been clearly demonstrated. The principal measurement, thecephalic index, does not appear always to correspond on the cranium and on the head of the living subject.A priori, the living head should have the index a little higher than the cranium, the muscles of the temporal region being thicker than those of the supra-occipital and frontal region. However, experiments made in connection with this subject are contradictory. According to Broca, two units must be subtracted from the index taken on the living subject in order to obtain the index on the cranium; this is also the opinion of Stieda and Houzé and a great number of anthropologists, while Mantegazza and Weisbach advocate the reduction of the index by three units; and Virchow and Topinard do not admit any. In the face of these divergent opinions, it is best to give the indices on the cranium and the living subject separately as they are, and indicate the rate of reduction or augmentation.
However, in a general way, one may admit, and I admit in this book, the difference of two units between the indices of the cranium and the living subject. In this way the two may be compared by adding these two units to the index of crania and removing them from the index of the living subject. I have given (p.57) the divisions of the cephalic index of the cranium; those of the living subject are the same with the addition of two units.
We may now proceed to examine a little more closely the principal measurements and the indices on the living subject by beginning precisely with thecephalic index, which I believe to be, in spite of the recent criticisms of Sergi[67]and Ehrenreich,[68]one of the good characteristics of race, enabling us to make some secondary partitions in the principal partitions of the genusHomo, based, as we shall see afterwards (Chapter VIII.), on the colour of the skin and the nature of the hair. Assuredly this index cannot express by itself alone the true form of the head or the cranium, but it supplies very clearly a first indication which gives a much better idea than detailed description, useful, to be sure, but rendering the study almost impossible when it is a question of comparing with one another a great number of different types. On the other hand, this index has such a fixity within the limits of any given race, that it is difficult to conceive how it could be dispensed with. The figures given by different authors when they rest on a sufficient number of subjects agree so much among themselves as to the cephalic index, that it is impossible to deny its fixity. The recent researches of Gonner[69]on one hundred children of Basel, far from weakening the assertion, as it would appear, speak in its favour; made on only the new-born or children one month old, they confirm what was already known, that the cephalic index varies with age, and by no means contradict its fixity. Ordinarily, at birth children appear to be more dolichocephalic than the adults of their race, but from the first month the head grows faster in breadth than in length; thus at the end of the first month, according to Gonner, the head is broadened in 52 children in 100, and remains stationary in 9 per 100. My own researches lead me to believe that the heads of children increase at first in breadth, to arrive afterwards gradually at a definite form, which is fixed about the age of ten, twelve, or fifteen years, according to race.
If instead of comparing, as Gonner has done, children of one month old with their parents, he had taken children from ten years upwards, he would have arrived at the same results as Spalikowski, who on forty-eight infants at Rouen found forty-one of which the cranial form corresponded with their parents. The researches of O. Ammon, Johansson andWestermarck, Miss Fawcett and Pearson, as well as my own (yet unpublished), lead to the same result.[70]
The differences of the cephalic index according to sex are insignificant. According to my personal researches, this difference hardly exceeds on the average 0.7 in the living subject and 1.5 in the cranium; and even this latter figure is exaggerated. It may, in a general way, be admitted that the difference between the cephalic index of men and women hardly exceeds one unit—that is to say, the degree of personal error in the observation. This difference is, in any case, less than the discrepancies between the different series of a single and homogeneous race.
In the table of the cephalic index which appears at the end of this volume (Appendix II.), however, I have given only the figures relating to men. A few series comprising individuals of both sexes appear there as exceptional cases. I have taken care to mark these with a letter S. In this table will be found side by side with indices taken on the living subjects some taken on crania, but no series contains measurements of crania and heads intermingled. The series of ten to twenty subjects or crania in the table appear there exceptionally, for the only series furnishing figures really exact are those comprising more than twenty individuals.
An inspection of the table shows us that there is a certain regularity in the distribution of the different cranial forms on the surface of the earth.
Dolichocephaly is almost exclusively located in Melanesia, in Australia, in India, and in Africa. Sub-dolichocephaly, diffused in the two extreme regions, North and South, of Europe, forms in Asia a zone round India (Indo-China, Anterior Asia, China, Japan, etc.), but is met with only sporadically in other parts of the world, especially in America. Mesocephalyis frequent in Europe in the regions bordering on the sub-dolichocephalic countries, as well as in different parts of Asia and America. Sub-brachycephaly, much diffused among the Mongolians of Asia and the populations of Eastern Europe, is very rare elsewhere. Lastly, brachycephalic and hyper-brachycephalic heads are almost exclusively limited to Western and Central Europe, to some populations of Asia, Turco-Mongols, Irano-Semites, and Thaï-Malays.
Has the form of the head, so far as the cephalic index can express it, an influence on the volume of the brain, and consequently on its weight, and even perhaps on the mentality? This question is subordinate to another, namely: To what point is the weight of the brain the expression of the psychical value of this organ? We shall see further, on p.101, that the weight can only be considered as a very rough approximation for the solution of psychological questions. But even in recognising in the weight of the brain the exaggerated importance that too long has been attributed to it, it may be said that it is not in relation with the conformation of the skull. The only investigation made into this matter—that of Calori—restricted to the figures of adults (from 20 to 60 years) by Topinard,[71]shows us that among Italian men the brachycephalic have on an average 27 grammes of brain more than the dolichocephalic, while among Italian women it is the dolichocephalic who have the better of the brachycephalic by 21 grammes. The differences in the two shapes being so very trifling, one may consider one’s self equally intelligent whether dolichocephalic or brachycephalic.
Next to the form of the head, that of the face is of great importance in recognising races. It may be more or less long or broad, oval (Fig.109), ellipsoidal (Fig.136), or round (Figs.119,164, and169), with soft contours or very angular, and then it may be found as an elongated rectangle (Fig.121) or a square (Fig.124); it may approximate also to the pentagonal form (Fig.17), etc.
Theforeheadmay be broad or narrow, low or high, retreating(oblique, Fig.21) or straight (Figs.24and90), it may present a medium protuberance, as for instance, among many Negro tribes (Fig.140), etc. Thesuperciliary archesmay be absent (Mongolian races) or very prominent, overhanging the eyes (Australians, Fig.15; Veddahs, Fig.5).
Thecheek-bonesmay be little developed (Europeans) or very prominent (Mongolians, Figs.17and20; Bushmen, Fig.24, etc.), but cheek-bones projecting forward must be distinguished from those developed laterally. Thechinmay be pointed, rounded, square, projecting, retreating (Fig.15), but these variations are of little importance, and may be found in conjunction with the most diverse forms of the face, while giving to it its own character. The posterior angles of the lower jaw may be more or less wide, and thus help to produce the angular contour of the face; quadrangular in the case of the square chin (Fig.121), or with pentagonal contour in the case of the pointed chin (Fig.118).
Theeyesfurnish also some differences of form. We distinguish the ordinary eye, as in our countries, and theobliqueornarrowed Mongolian eye. The latter presented in its most perfect form is characterised as follows. It is placed obliquely, so that its external angle is higher than its inner angle (Fig.121). This disposition is due to the too high attachment of the external palpebral ligament to the skull, as Regalia has shown.[72]Its palpebral aperture is much narrower than in the ordinary eye, and instead of having the form of an almond, it has rather that of a scalene triangle (Figs.18and118) or of a little fish whose head corresponds to the inner angle (Fig.119). But these peculiarities are not the most important, and may be met with, though rarely, in ordinary eyes. The essential characters of the Mongolian eye consist, as Metchnikof[73]has shown, in a puffiness of the upper eyelid, which turns down at the inner angle of the narrowed eye, and, instead of being free, as in the ordinary eye, is folded towardsthe eyeball, forming a fixed fold in front of the movable ciliary edge; this last becomes invisible and the eyelashes are scarcely seen. Moreover, towards the inner angle of the eye, the eyelid forms a fold covering more or less the caruncula, and sometimes extending more or less far below (Fig.18). These peculiarities, which can be met with quite often among the children of all races as a transitory characteristic, may be explained up to a certain point by the very small development of the pilous system in general in people among whom they persist. For among Europeans, for instance, the inversion of the eyelid (entropion) may become a cause of disease (trichiasis) precisely on account of the growth of the eyelashes.[74]