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Characteristics of the brain of the Mongol race.

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CHARACTERISTICS O F T H E BRAIN O F THE
MONGOL RACE
Institute of
N. BUSHMAKIN
Anatomy, University of Irkoutsk, giberia
FIVE FIGURES
Until now the anthropological study of the brain has not
yet included small nations, especially those belonging to the
Mongol race. Therefore, being at work for the last years in
the University of Irkoutsk and having assembled a considerable collection of brains belonging to Siberian nations (above
300), we have devoted a special attention to the brains of
Buriats, as they have never been described as yet and as there
is a most regular though slow addition of Buriat brains to
our collection.
The Buriats are a nation belonging to the Mongol race;
their number is comparatively small, amounting to 215,000,
according to the last census; they live near Lake Baikal.
Their physical type has been rather well studied (Shondrikowsky, Porotoff, Talko-Hryiitzewitsch). The Buriats are of
average stature, sometimes even lower. Straight black hair,
absence of beard, and scantiness of hair on the body are the
characteristic signs of the Mongol race. The thickness of the
Buriats’ hair is moderate-not more than 110 to 120 hairs on
a square centimeter; it begins to get gray rather late-at
forty-five to fifty years; but it sometimes happens that the
hair keeps its black color even in old age-past
sixty to
seventy years. We must emphasize the marked persistence of
the hair, never having met with bald men. I n the central part
of its length the thickness of a Buriat’s hair varies from 60.0
to 93.6 mm. ; the color of the pigment of the cortical layer in
the bulbous part of the hair is gray-brown on a transparent
221
AMERICAN JOURNAL O F PHYSICAL ANTRROPOLOQY, VOL. XII, NO. 2
OCTOBER-DECEMBER, 1928
222
N. BUSHMAKIN
gray or yellowish ground. This coloring of the bulbous part
is a characteristic feature for the hair of a Buriat; it does not
vanish when subjected to a treatment with a 3 to 4 per cent
solution of hydrogen peroxide. The form of the transverse
section of the hair of a Buriat is elliptic in 44 per cent of the
cases, irregularly round in 20 per cent, and triangular in 11
per cent; in all other cases the hair has a concavity on one
Fig. 1 Types of Buriats.
side or on both (Grigorieff). The color of the skin is pale
yellow with a brownish shade in the uncovered places. The
eyes are hazel-brown, but the Mongol fold is invariably present. The face is either broad or oval; the nose, short, broad,
and flattened. The interocular area is mostly broad. The
ears are not large.
The Buriats are typical brachycephalics; there are no
dolichocephalics to be met with.
THE BRAIN O F THE MONGOL RACE
223
The molar diameter is relatively large; the volume of the
skull attains 1702 cc. Most of the skulls of Buriats show an
asymmetry of the skull and a torus occipitalis (Kaxantzewa).
The circumference of the chest exceeds half the stature,
though not much. The body is of average length ; the breadth
of the shoulders, considerable. The arm is long, the feet of
average length, often crooked. The larynx of the Buriats
offers the following peculiarity: the angle of the thyroid cartilage is smaller and more persistent than in Russians and
Fig. 2
Types of Buriats.
Chinese. The ossification of the cartilages of the larynx
proceeds slowly and is belated in comparison to Russians
(Sinakowitch). The pelvis of the Buriat woman is like that
of the Russian, with a certain diminution of the anteroposterior dimension (Bushmakin).
The biochemical race-indicator of blood for Buriats, calculated according to Hirzsfeld’s formula, is 0.65, approaching the formula for Koreans and partially for Chinese
(Melkich) .
We have at our disposal thirty-five brains of Buria.ts.
224
N. BUSHMAKIN
I n order to characterize the brain of a certain nation it is
necessary to begin by determining its weight.
The question of the weight of the brain is of very long
standing; Aristoteles has already pointed out that the male
brain is heavier than the female.
There are numerous researches on the influence exercised
by race on the weight of the brain.
According to Schwalbe, the brain of a European man
weighs on the average 1375 grams and the brain of a European woman, 1245 grams. As to its weight for different
nations inhabiting our republic, we have according to Guiltchenko (700 weighings) the following average weights :
Russians,
Ukrainians,
Poles,
Germans from different regions,
Armenians,
Tchetchens,
Georgians,
Jews,
Wotiaks,
Zyrians,
Tcheremiss,
Tchuwash,
Bashkirs,
Tartars,
Number of
Grllm.9
observatiom
1367.9
1365.6
1397.2
1390.5
1369.8
1462.9
1350.4
1336.7
1437.7
1415.6
1294.1
1439.9
1414.6
1386.3
221
133
102
16
12
17
11
23
8
16
7
7
11
9
Birula-Wolynitzky gives for the Slavic nations inhabiting
our republic a slightly higher weight of the brain-1409.7
grams.
The weight of the brain of Buriats is, on the average,
1508 grams for men and 1439 grams for women. Thus, we
must place the brains of Buriats in the category of heavy
ones; by their weight they surpass considerably the brains
of Europeans. These data coincide with the deductions of
Talko-Hryntzewitsch, who, having had the opportunity of
weighing twenty-six brains of Buriats ( twenty-f our masculine
and two feminine), came t o the conclusion that the Buriats
had brains of considerable weight, both absolutely and rela-
THE BRAIN O F THE MONGOL RACE
225
tively to their stature. He determines the average weight
for the brains of Buriats as 1423.4 grams, i.e., slightly lower
than in our cases. If we join our data to this author’s material, we shall have sixty-one Buriat brains, of which fifty
are masculine and eleven feminine, with the average weight
1485 grams f o r men and 1438 grams for women. I n 86 per
cent of cases the weight of the brain of a Buriat is higher
than the average weight of the brain of a European; there
are some exceedingly heavy brains; so, for instance, the
weight of the brain of one thirty-year-old Buriat was 1934
grams. The brain of Buriat women in all cases is higher than
the average weight of the brain of European women.
The lightest weight of the brain was found in a sixty-yearold Buriat ; it amounted to 962 grams.
It is interesting to note the insignificant difference between
the weight of the masculine and feminine brains, this difference amounting only t o 47 grams, whereas for Europeans it
amounts to 100 to 150 grams. Perhaps this slight difference
of weight between the brains of men and women can be accounted for by the fact that the Buriat woman performs the
same work as the Buriat man.
The influence of the stature and of the weight of the body
on the weight of the brain-as yet not solved by far-may
perhaps be illuminated by the grouping of material according to races. We can see in the brains of Buriats a vivid
example of the dependence of the weight of the brain first of
all on race, and not upon stature. I n fact, the Buriats are
of average stature or even in most cases below it, whereas the
weight of their brain surpasses considerably the weight of
the brain in Russians, whose stature is higher than that of
the Buriats.
Within the limits of one tribal group, in the present case
amid Buriats, in spite .of the scantiness of observations, it is
easy to see that with the increase of stature the absolute
weight of the brain generally increases too, though without
direct proportionality.
226
N. BUSHMAKIN
The dependence of the weight of the brain on the form
and the volume of the skull is fully confirmed by studying
the Buriat brain. I t s great weight fully corresponds to the
greater volume of the Buriat skull, which, according to
Kasantzewa’s craniometrical measurements, amounts to
1702.5 cc. The Buriats, typical brachycephalics, have the
heaviest of all brains; this confirms the remarks of many
ancient scientists that the brain of brachycephalics is heavier
than that of dolichocephalics.
According to Broca’s observations, we can admit that the
weight of the brain increases in time under the influence of
culture, but within the limits of this or that tribal group.
However, this remark does not give us the right to judge of
the culture of different nations by the weight of their brain,
as the weight of the brain depends chiefly on the race. The
Buriats have entered the zone of cultural development only
with the new state organization ; nevertheless, their brain
surpasses that of Europeans ! Nucke’s statement that the
increase of the weight of the brain rises from savages to
civilized men and from ordinary men to geniuses is nothing
but the result of a misunderstanding.
The average weight of the cerebellum is 143.6 grams and
the difference of weight in men and women is utterly insignificant ; the relative weight of the cerebellum compared
to the weight of the whole brain of women is even slightly
higher than in men.
The average weight of the pons is 17.1 grams and of the
medulla, 5.7 grams, so that both in men and in women these
parts of the brain have almost the same weight. The relation
of the weight of these parts t o the weight of the whole brain
and the comparison of these relations in different nations
afford interesting data, but the scantiness of the material
obliges us, for the present, to refrain from any deductions.
Apparently, the average weight of the brain, the relation
of its different parts to the weight of the whole brain, a s well
as the relation of the weight of the whole brain to the stature
and weight of the body, are persistent race signs f o r each
THE BRAIN OF THE MONGOL RACE
227
nation, and only considerable individual deviations strongly
veil these relations. The elucidation of the influence of
stature, sex, and age on the weight of the brain must be made
only within the limits of one race, since only observations of
this kind can give definite concrete results.
It is necessary to make certain remarks on the technique of
the weighing of the brain.
Some investigators weigh the brain with its pia mater,
washing the brain all over with water; others take it off;
the third method is to incise the ventricles (Engel) in order
to remove the cerebral fluid which they contain. Reid1 did
not remove the brain a t once for his weighings, but first
gradually cut off the superior part of the hemispheres down
to the ventricles, after which, having previously removed the
fluid from them, he extracted the other parts of the brain
and, then only, weighed the whole.
Robert Boyd extracted the brain for weighing in the following way: H e severed first the whole superior part of the
brain, cutting it off in slices down to the tentorium cerebelli;
then, having extracted the cerebellum with the pons and the
medulla oblongata, he weighed these parts separately. However, there have been authors who did not make a direct
weighing, but defined the weight of the brain by means of
calculation from the volume of the brain, proceeding from
the supposition that the volume of the brain always exactly
corresponds to the weight of the brain. I n this manner Davis
composed a table of the weight of the brain of all the races
of the earth, having defined the average weight of the brain
for European men as 1367 grams, for women as 1204 grams;
for African nations: men, 1293 grams, and women, 1211
grams.
The last method must be abandoned as lacking precision;
because, as has been ascertained by further researches, there
is no strict proportionality between the weight of the brain
and the volume of the skull.
The method of cutting slices from the hemispheres and of
preliminary section of the ventricles is rather intricate with-
228
N. BUSHMAKIN
out offering any advantages, for which reason it is seldom
used.
We cannot recommend the removal of the pia mater, as has
been done by many authors (Tiedemann), because the removal of it from the fresh brain is rather troublesome and
requires very much time.
It is just as unnecessary to wash the brain with water
(except in case of some special indications, when it is covered
with pus or with coagulated blood as in cases of wounds),
the simple process of washing leading to an increase of
weight.
The observations of Gorodinskaya in our Institute have
proved that the stay of brain in cold water during twentyfour hours adds 100 to 150 grams to its weight and the stay
for forty-eight hours, 200 grams. If this be the case, the condition of the pia mater is not indifferent; in case of its
rupture or of its severing, though partial, and still more in
case of a wound on the brain itself, the weight of the latter
increases still more rapidly.
The weight of the brain lying in formalin increases during
a month more than 300 grams; then, after a month in formalin
and sometimes even earlier, there ensues a slow loss of
weight, till some years later the weight of the brain lying in
formalin becomes even lower than its primary weight.l
According to our observations, some brains that have been
lying in formalin during four to five years have lost 100 to
150 grams of their primary weight; and Kapoustin, who has
had the chance twenty-two to twenty-four years later of
renewing the weighing of the brains having belonged to deceased professors of the Moscow University, found that they
had lost in weight from 125 to 248 grams.
Brains put into alcohol certainly lose part of their weight,
especially during the first days.
The best fluid for conserving brain is a 10 per cent formalin
solution.
See Hrdli6ka (Alek) : Brain and Brain Preservatives; Proc. U. S. Nat. Mus.,
1906, XXX, 245-320.
THE BRAIN O F THE MONGOL RACE
229
The sums given by separate investigators for the weights
of the brain of different nations are very dissimilar. This
depends on the technique, as well as on the time of the weighing and on very considerable individual divergences in the
weight of the brain. It is absolutely urgent to make a comparison of the average weight of the brains of different nations, grounded on numerous observations of individuals of
the same sex, age, stature, and weight of the body. The
divergences of weight of different parts of the brain of separate nations are also worth attention; this has been pointed
out by several investigators (Bischoff, Weisbach).
As to the weight of both hemispheres, as has been proved
by the observations of Braune and for children's brains by
the observations of Pfister, in most cases one-half of the
brain is some grams heavier than the other and oftenestthe left one. According to our own observations, the left
hemisphere of the Buriat 's brain weighs more than the right
only in 56 per cent, and even then the difference does not
exceed 5 to 14 grams; in all other cases both hemispheres are
of the same weight or the right is even heavier than the left.
Talko-Hryntzewitsch has found a predominance in the weight
of the left hemisphere in Buriats in 39.1 per cent and, according to Guiltchenko, f o r Russians from European Russia the
weight of the left hemisphere surpasses the weight of the
right only in 19.8 per cent.
We attach a great importance to the difference of weight
of the hemispheres and suppose that it arises from the prolonged influence of culture. There is no doubt that cultivated
habits lead to a differentiation of the upper extremities, most
precise movements necessary for modern man for writing or
for the management of delicate instruments being required
from one of them. These complex movements are effected in
most cases by the right extremity, that is, under the influence
of the left hemisphere; therefore, we may suppose that part
of the overweight of the left hemisphere may depend on the
degree of culture. We must add that, as was shown by the
researches of Godinoff in our Institute, the left hemisphere
230
N. BUSHMAKIN
has a magistral type of distribution of the vessels, and that
these a r e of a larger caliber than those of the right hemisphere.
After the weighing, or before it, the fresh brain is subjected to lineal measurement; here it is generally measured
in both largest dimensions, longitudinal and transverse ;
other investigators advise making these measurements only
when a sufficient solidification of the brain in the preserving
fluid has already taken place.
Neither of these systems yields sufficiently precise results
or may be deemed entirely trustworthy. I n the first case, the
fresh brain, being often oedematous and apt to spread, does
not admit of precise measurements ; in the second, the solidified brain, having already partly lost its primitive form, cannot yield the precise measure of the brain. Talko-Hryntzewitsch, who has performed measurements on fresh brains,
gives the following average size of the cerebrum:
Buriats,
Russians,
Longitudinal
mm.
Tranucersc
mm.
161.5
158.7
142.9
133.3
Average size of the cerebellum :
Buriate,
Russians,
Longitudinal
mm.
Tranavcres
mm.
68.7
72.1
109.8
107.0
However doubtful these data, they still indicate the probable race difference between Buriats and Russians, corresponding to the form of the skull. F o r the cerebellum, Guiltchenko gives much larger average sizes for the various tribes
of Russia : longitudinal measure, 83.8 mm. ; transverse, 114
mm.
According to our measurements, the average length of the
hemispheres, right as well as left, is 170 mm. ; the left hemisphere exceeds the right only in 38.7 per cent of the cases.
I t is interesting to record that Weinberg, who has studied
the brains of Poles, asserts that the hemispheres of the brain,
with only ra r e exceptions, are of rather unequal length and
T H E BRAIN OF THE MONQOL RACE
231
that the length of the left hemisphere always exceeds the
length of the right, even if only by some millimeters.
As to the sizes of separate lobes, the length of the frontal
lobe varies from 136 to 111 mm., the parietal and occipital
lobes from 69 to 44 mm. It is evident that the difference of
length of separate hemispheres depends principally on the
length of the frontal lobe.
The length of the corpus callosum is 76 111111. on the average.
We have never chanced to notice a large difference between
men and women. W e must state that the form of the corpus
callosum, its curves, and thickness in different parts a r e most
variable. We have not had the chance of establishing types
of the corpus callosum, a s the material has been very limited.
The measurement of the volume of separate hemispheres
has yielded the following results: for the left hemisphere, on
the average, 647 cc. ; for the right, 618.2 cc. ; the volume of the
left hemisphere exceeds .the right in 40 per cent of the cases.
When studying the brains of races, we attached the greatest
importance to the peculiarities of the relief of the cortex.
Since Tiedemann, who has attempted to find typical furrows
in negroes and Bushmen, investigators have undertaken numerous observations devoted to this problem.
We must mention the classic work of G. Retzius, richly
illustrated with beautiful plates and devoted to the macroscopic morphology of Swedes; a similar work has been performed by Giacomini on the brains of Italians, by Marchand
and Handmann on Germans, by Weinberg on the brains of
Poles, Lithuanians, and Jews ; Zernoff, Birula-Balynitzky, and
Guiltchenko have worked on Russian brains.
The anthropologist Buschan states that the human brain,
whether it belong to an inhabitant of the Fiery Island or to
a Papuan, to a Russian o r to a German, presents the same
structure and the same variations in all degrees of culture.
Thus, all investigators who look for t,ypical race furrows have
met with disappointment, and Kohlbrugge, for instance, has
come to the entire negation of any importance in the position
of furrows for the discernment of races.
232
N. BUSHMARIN
On this ground, had we not better abandon studying the
relief of the cortex and base all our hopes on the study of
the inner structure of the brain, its architectonics? Certainly, no! A t present, even though the explored material is
most insignificant, we have still attained to one undisputable
and most important conclusion-that the distinction of race
by the relief of the brain is reduced not to the qualitative side
of the question, but to the quantitative one, i.e., that some
varieties a r e oftener met with in one race and others in
another. I n the general characteristics of the brain of each
nation, the peculiarities of the folding of the cortex will
doubtlessly receive their definite place. W e inust add, too,
that, with the exception of the study of the disposition of
separate furrows, our principal attention must be devoted to
the general topography of the cortex: the basal direction of
the furrows, their depth, quantity, and their symmetrical
distribution.
Passing now to the characteristics of the relief of the hemispheres of the Buriats’ brain, we have the possibility of
noting the following peculiarities :
1. The gyrification is always considerable; the furrows of
the first and second category a r e sharply outlined and sufficiently deep. The presence of a considerable quantity of
furrows of the third order gives a complex picture of the
sinuosities and folds of the cortex. There a r e some brains
with a very great abundance of small sinuosities, as we have
found, f o r instance, on the brain of a seventeen-year-old
Buriat, reminding us of the brain of the mathematician
Hauss.
2. We have found a moderate asymmetry in all brains.
3. I n all Buriat brains there prevails a transversal type of
furrows that is particularly evident in the parietal and occipital lobes.
4. As to separate furrows, it is necessary to make here the
most important remarks.
The length of the fissure of Sylvius (fissura lateralis
cerebri) varies considerably, as well as its position and end-
THE BRAIN O F THE MONGOL RACE
233
ing; it may be disposed almost horizontally, or it may rise
steeply with its posterior end into the parietal lobe ; the posterior end may have a n ascending or a descending branch, or
again it may break off abruptly without any branches. The
anterior ascending branch (ramus anterior ascendens) is
mostly single.
Weinberg reports in the brains of Poles a greater length of
the exterior o r posterior branch of the fissure of Sylvius on
the left hemisphere (62.5 mm.) when compared to the right;
we lack the possibility of proving the same difference on the
brains of Buriats; in two cases only the islet was not entirely
covered.
W e have abstained from a detailed investigation of the
islet, wishing to secure the integrity of the scanty material
we were examining, as an investigation of this kind inevitably
requires the removal of a considerable amount of cerebral substance.
As to the central furrow, i t cuts through the medial edge
of the hemisphere only in 59 per cent of the cases. After
having studied 400 hemispheres, Eberstaller states that cases
when the central furrow comes to a n end without attaining
the superior edge of the hemisphere a r e quite exceptional.
Retzius has found in Swedes that this furrow does not reach
the edge of the hemisphere in 20 per cent of the cases. According to researches made by Kurz on brains of Chinese,
this furrow attains the medial edge only in 15 per cent of
the cases-which may be evidently ascribed to the insignificant development of the surface of the brain of the Chinese.
This divergence may be apparently interpreted by the influence of tribal peculiarities of the brain.
The medial frontal furrow (sulcus transversus medius)
has been observed in 72 per cent of the cases. A type of
brain of this kind with three frontal furrows is very near to
the type of brains of inferior apes. This furrow is often encountered in Europeans; we have had the occasion to see it
on the brains of many nationalities of our republic. Certainly
it cannot be looked upon as a distinctjive peculiarity of criminals, as was supposed by Benedikt.
234
IT. BUSHMAKIN
There is a considerable abundance of short transverse furrows on the whole frontal lobe.
As is generally the case, the precentral and postcentral
furrows vary immensely.
I n our collection the interparietal furrow has been found
in all varieties by investigators during the study of the brains
of different races. I n more than half the cases it falls into
several segments.
The transverse occipital furrow has been seen on the hemispheres of the brains in our collection in 80 per cent of the
cases (sulcus occipitalis transversus of W'ernicke). As is well
known, attention was directed to this furrow long ago, and
it is supposed to be analogous to the Affenspalte of German
anatomists. Being a persistent and characteristic furrow of
the brain of apes, it appears in a great variety of forms in
diff erent anthropoids. Some authors have denied its presence
in the human brain or have found it in extremely rare cases.
Our Russian Professor Zernoff did not think it typical; and
it has been encountered more frequently only since the study
of the brains of different nations has been conducted on a
broader scale; Kurz has found i t on almost all Chinese brains
that he investigated.
When found on human brains, the transverse occipital furrow offers an immense variety of outlines, extension, and
depth; in consequence, it bears many names : sulcus occipitalis
transversus, sulcus anterior, sulcus parieto-occipitalis parietalis; this has brought about much perplexity. We have
found it in the brains of Russians, Poles, Armenians, Jakouts,
Koreans, Chinese, and Buriats.
I t s diverse varieties may be reduced to f o u r types:
T y p e I . The transverse occipital furrow is, so t o speak, a
continuation of the parieto-occipital fissure (fissura parietooccipitalis) ; the latter, having cut very deeply into the medial
edge of the hemisphere, passes in these cases directly into
the transverse occipital furrow. We have found this type in
our collection in 40 per cent of the cases.
THE BRAIN OF THE MONGOL RACE
235
T y p e 11. The transverse occipital furrow is independent,
either in the form of an arc or in the form of a straight line,
lying in the contiiiuation of the fissura parieto-occipitalis.
T y p e 111. The transverse occipital furrow is joined by its
inferior end to the superior temporal furrow, becoming seemingly its direct continuation. The last type is often met
with in our collection.
Weinberg supposes that the anastomosing of the transverse
occipital furrow (Wernicke) with the superior temporal furrow is a characteristic peculiarity of the brain of Poles; in
this case the latter bends continuously into the former with
its posterior segments.
T y p e ZV. Having started from the medial edge of the hemisphere, where this is split by the fissura parieto-occipitalis,
the transverse occipital furrow passes on without interruption to the inferior edge, in the form of a deep arc, bearing in
this manner a complete similarity to the furrow of the ape.
This type is to be seen only in exceptional cases; in our collection we have seen it only in four hemispheres.
The transverse occipital furrow has a close relation to the
interparietal furrow; both these furrows may interrupt each
other by bridges or simply cross each other. I n some cases
the transverse occipital furrow may consist of small segments, the characteristic feature of which is that they lie on
the margin of the occipital and parietal lobe, on the line that
serves a s a continuation of the fissura parieto-occipitalis down
to the inferior edge of the hemisphere.
According to our own observations, the temporal lobe attains a moderate development; the superior temporal furrow
has been found in all hemispheres and was interrupted in
9 per cent; the medial (second) temporal furrow has been
seen only in 22 per cent and was interrupted in half the cases.
On the inferior surface, the furrows of the orbital region
present, a s usual, a most inconstant arrangement, thus rendering it utterly impossible to discern any type whatever.
The collateral fissura is to be found on all hemispheres ; it
proceeds without interruptions (on Chinese brains it is often
interrupted, Kurz) .
236
N. BUSHMAKIN
As to the third temporal furrow, it is to be seen only in
27 per cent, and in almost all cases on the left hemisphere
(it has been found only once on the right). Zernoff has found
it in the brains of Russians in 56 per cent of the cases; on
the medial surface the encircling sinuosity is divided into
Fig. 3 Occipital lobe of the right hemisphere of a Buriat’s brain.
sulcus occipitalis transversus; interpar., sulcus interparietalis.
oc.tr.,
two segments in 22 per cent of the cases; in 18 per cent it is
double either in its whole extent or only in its anterior part.
I n 27 per cent of the cases the fissura calcarina is joined
to the fissura hippocampi (as by anthropoids) ; in the Chinese
they join only in 15 per cent.
I n 30 per cent we meet with a bifurcation of the superior
end of the fissura parieto-occipitalis.
THE BRAIN O F THE MONGOL RACE
237
Almost in all cases the olfactory area on the brain of
Buriats-gyrus
subcallosus, area parolfactoria, stria longitudinalis et uncus-is sharply outlined and attains a considerable size. This circumstance is worth attention, if we
remember that the Buriats, for instance, detect the smell
of smoke at a very great distance. In valleys the Lamas
collect, very cleverly, different herbs with a whole scale of
Figure 3 A
agreeable scents, and a Buriat mother does not kiss her child,
but smells it. Apparently, the organ of smell has a greater
significance for Buriats than for Europeans.
We are in the habit of associating a high intellect with a
great gyrification. Numerous descriptions of the brains of
famous men, which appear now and then, prove that the
peculiarities of the brain are reduced in these cases to the
following features : considerable weight, strong gyrification,
AMERICAN JOURNAL O F PHYSICAL ANTHROPOLOQY, VOL. X I I , NO. 2
238
N. BUSHMAKIN
Fig. 4 Left hemisphere of a Buriat’s brain. F.Zat., fissura cerebri lateralis;
cent., sulcus centralis ; f.sup., sulcus frontalis superior; f.med., sulcus frontalis
medius ; f.inf., sulcus frontalis inferior; interpar., sulcus interparietalis; oc.tr.,
sulcus occipitalis transversus.
Fig. 5 Frontal lobe of the left hemisphere of a Buriat’s brain. F.Zat., fissura
cerebri lateralis ; cent., sulcus centralis ; praec., sulcus praecentralis ; f.sup., sulcus
frontalis superior; f.med., sulcus frontalis medius; f.inf., sulcus frontalis inferior.
T H E BRAIN OF THE MONGOL RACE
239
and some particular deviation of the furrows of the brain.
The attempt to combine superior intellect with some particul a r deviation of the furrows has proved to be hopeless and
Figure 4 A
must be entirely abandoned, nobody having ever described a
deviation of a furrow that has not been frequently met with
in the brains of ordinary men.
240
N. BUSHMAKIN
A considerable weight and a great degree of folding on
the cortex may often fail in the brains of famous men; for
instance, the brain of Sophia Kowalewskaya-a
mathematician (described by Retzius)-was of a very primitive kind
and poor in furrows, and the brains of Bunsen, Mentzel, and
many other famous men weighed less than the usual norm
(1295 t o 1298 grams).
On the other hand, all anatomists know how often they
happen to see in institutes of anatomy-in subjects used f o r
dissection-brains of considerable weight and with a strong
gyrification, belonging to quite obscure men who during their
lifetime had never been remarkable in any way. Weight and
great number of folds on the cortex a r e first of all features
of a hereditary or tribal order; therefore, noting these
features on the brains of one or another nation, we a r e far
from the thought of connecting them with a high degree of
endowment, which depends equally on the general constitution
of the body and is defined by the biochemical properties of
the whole organism.
It will be opportune to recall here the opinion of Galen,
according to which it is the quality of the brain, and not its
relative dimensions, that must have the preeminent importance.
I n what light do we consider the peculiarities that we have
remarked in the relief of the Buriats’ brain? Do we regard
them as tribal? It is exceedingly difficult to give a categorical
answer to this question, by reason of the lack of material;
nevertheless, we a r e inclined to the view that these peculiarities bear a tribal character. The comparison of the Buriats’
brain with the brains of other nations, pers.onally studied by
us o r described by other authors (Weinberg, Retzius, Giacomini, Zernoff, and others), gives us the right to do this.
W e think that in the general characteristics of the brain of
every nation the description of the cortex is absolutely necessary. The errors of earlier investigators consisted partly
in the fact that they attempted to reduce all tribal distinctions to the diversity of furrows, though they were supported
THE BRAIN OF THE MONGOL RACE
241
by very limited material (three to five to ten brains). It is
not to be wondered at, that in proportion as they drew into
the orbit of their researches a greater amount of brains from
different nations, their deductions proved wrong in many occasi ons.
As to the inner structure of the Buriats’ brain, its peculiarities amount principally to the following :
The size of the rhomboidal fossa varies greatly, and the
index of its breadth, meaning the relation of breadth to
length, oscillates from 58 to 78; a similar strong oscillation
of the index of the rhomboidal fossa is observed in Japanese
brains (Schimada). The area acustica at the bottom of the
rhomboidal fossa contrasts sharply in most cases (in 88 per
cent).
We have also remarked an almost constant inequality of
the olives.
We have found in our collectioii most interesting varieties,
springing from the circumstance that the streaking of the
pyramidal fibers begins very high, in close proximity to the
pons.
The acoustic streaks (striae acusticae) a r e mostly disposed
unsymmetrically and ar e most variable a s to their breadth.
Concerning the study of the race architectonics of the brain,
it is as yet untimely to speak of conclusions, by reason of the
extreme complexity of such investigations. But we may say
with security that it is unlikely that divergencies will be found
in the architectonics of the brains of different nations.
To conclude, we must state that the study of the brain
according to race can be attained only when we will possess
the characteristics of the brain of all nations and of all tribes.
These characteristics must be complete and give us indications as to its sibe, relief, inner structure, and architectonics;
for i t is only by means of comparison of full series of characteristics that we can clear up the race features of the brain
of different nations. The anthropological research of the
brain, says Waldeyer, will improve only when thousands of
brains of the most varied classes of the population have been
242
N. BUSHMAKIX
subjected to investigation according to an established general
plan. It is also desirable that the subjects examined be well
known according to their psychical, physical, and other peculiarities. I t is necessary, therefore, to assemble in corresponding scientific institutions vast collections of brains,
side by side with the existing craniological collections.
With the cerebrological characteristics of each separate
nation, it is necessary to study in parallel its psychical peculiarities, which will afford us the possibility of comparing
its psychological type with the morphological features of the
brain.
The characteristics of the Buriats’ brain may be summed
up as follows:
1. As to volume and weight, the Buriats’ brain is excessively large and heavy.
2. The sexual difference of the weight of the Buriats’ brain
is insignificant.
3. The Buriats’ brain has considerable transverse dimensions.
4. On the Buriats’ brain the prevailing type of disposition
of the furrows is the transverse.
5 . The transverse occipital furrow on the Buriats’ brain is
persistent and is much better marked than on other nations’
brains.
6. The medial frontal sinuosity is just as persistent.
7. The olfactory area is always well marked.
8. The index of the rhomboidal fossa varies to a great
degree.
THE BRAIN OF T H E MONGOL RACE
243
BIBLIOGRAPHY
BISCHOFF,TH. 1880 Das Hirngewicht des Menschen. Bonn.
BRAUNE,
W. 1891 Das Gewichtsverhaltniss der rechten zur linken Hirnhalfte
beim Menschen. Arch. Anat.
BUCHSTAB,I. 1884 Materials to the problem of the weight and volume of the
brain (in Russian). St. Petersb.
N. 1899 Weight of the brain and of some of its parts i n
GUILTCHENKO,
several tribes inhabiting Russia (in Russian). Works of the Anthropological Section, Moscow.
EBERSTALLER,
0. 1890 Das Stirnhirn. Wien und Leipzig.
K U R Z 1924 Das Chinesengehirn. Verh. anat. Ges., Berlin.
RETZIUS,
G. 1896 Das Menschenhirn. Stockholm.
SNITH,G. 1904 The so-called Affenspalte in the human brain. Anat. Anz.,
XXIV.
WF,lh?mQ, R. 1905 Die Gehirnform der Polen. Z. Morph. u. Anthrop., VIII.
TALKO-HRYXTZEVITSCH,
J. 1909 Some d a t a as t o the weight of the brain of
the inhabitants of the Transbalcalian Region (in Russian). Works
of t h e Troitskosawsko-Kiachta Section of t h e Society of Geography,
I X , issue 2.
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