Part 39

These facts are probably of more significance than might seem at first glance; for it is precisely by the same characters, carried still further, that some of the Eskimo differ from others. Let us compare two of our largest and best groups, those of St. Lawrence Island and Greenland:

+---------+--------+---------+--------- | Number | Skull | Breadth | Height |of skulls| length | | | (both | | | | sexes) | | | ---------------------+---------+--------+---------+--------- St. Lawrence Island | (293) | 18.05 | 13.90 | 13.45 Greenland | (101) | 18.51 | 13.30 | 13.54 ---------------------+---------+--------+---------+---------

The Greenland skull is longer, narrower, and somewhat higher. The differences are less than those between a child and an adult western Eskimo, but of the same nature. This apparently speaks strongly for the development of the Greenland type of Eskimo cranium from the western. On the other hand, the type of skull shown by the Eskimo child approaches much more closely than that of the Eskimo adult to the type of the skull of the Mongol.

The above are mere observations, not theories, and they carry a strong indication that mostly we are still floundering only on the borders of true anthropology, embracing all phases of life and development, which, if mastered, would give us with beautiful definition many now vainly sought or barely glimpsed solutions.

A highly interesting feature is the relatively great development in the Eskimo, between childhood and the adult stage, of the anterior half of the skull or basion-nasion dimension. This augments, it is seen, by even 3.4 per cent more than the length. This growth must involve some additional factor to those inherent in the bones themselves and in the attached musculature, and this can only be, it seems, the development of the anterior half of the brain. Evidently this portion of the brain between childhood and adult life grows in the Eskimo more rapidly than that behind the vertical plane corresponding to the basion. It is a very suggestive condition calling for further study, and thus far almost entirely wanting in comparative data on other human as well as subhuman groups.

FOOTNOTES:

[160] Same group for adults as for children.

THE LOWER JAW

The lower jaw of the Eskimo deserves a thorough separate study. For this purpose, however, more jaws in good condition are needed from various localities, and particularly more jaws accompanying their skulls. As it is, a large majority of the crania are without the lower jaw, or the alveolar processes of the latter have become so affected in life through age and loss of teeth that their value is diminished or lost. Still another serious difficulty is that the measuring of the lower jaw is difficult and has not as yet been regulated by general agreement, so that there is much individualism of procedures with limited possibilities of comparison.

One of the principal measurements taken on the available Eskimo mandibles was the symphyseal height. This is taken by the sliding calipers and is the height from the lower alveolar point (highest point of the normal alveolar septum between the middle lower incisors) to the lowest point on the inferior border of the chin in the median line.[161] The results are given in the following tables.

ESK̅IMO LOWER JAW: HEIGHT AT SYMPHYSIS

+------------------------+------------------------ | Male | Female ---------+-------+-------+--------+-------+-------+--------

Groups | South-|North- |Northern| South-|North- |Northern (main) |western|western| and|western|western| and | and| | eastern| and| | eastern | mid-| | | mid-| | |western| | |western| | | | | | | | | (9)| (5)| (5)| (9)| (5)| (5) | | | | | | Specimens| (116)| (143)| (40)| (121)| (134)| (25) | | | | | | Average | 3.75| 3.76| 3.67| 3.38| 3.34| 3.39 | | | | | | General | 3.76 | | 3.36 | mean in | | | | western | | | | Eskimo | | | | | | | | Percental| _89.4_ relation | of | female | to male | (M = 100)| ---------+-------+-------+--------+-------+-------+--------

+------+-------- |Males,|Females, | 19 | 19 |groups| groups | (399 | (280 |jaws) | jaws) ------------------------------------------------------+------+-------- General mean for all Eskimo (approximate) | 3.73 | 3.37 | | Percental relation of female to the male | | _90.4_ | | General mean of total facial height |12.47 | 11.60 | | Percental relation of height of jaw to total facial | _30_ | _29_ height | | | | General mean of upper facial height | 7.76 | 7.20 | | Percental relation of height of jaw to upper facial | _48_ | _47_ height | | ------------------------------------------------------+------+--------

Just what these figures mean will best be shown by a table of comparisons.[162] All these are my own measurements.

LOWER JAW OF VARIOUS RACES: HEIGHT AT SYMPHYSIS

+------+------+------------- | | |Female versus | Male |Female| male | | | (M = 100) -------------------------+------+------+------------- | (399)| (280)| Eskimo (all) | 3.73| 3.37| _90.4_ North American Indians: | (36)| (26)| Sioux | 3.60| 3.22| _89.4_ | (52)| (50)| Arkansas | 3.66| 3.24| _88.5_ | (29)| (21)| Florida | 3.69| 3.38| _91.4_ | (9)| (6)| Munsee | 3.70| 3.40| _91.9_ | (15)| (14)| Louisiana | 3.72| 3.29| _88.4_ | (44)| (30)| Kentucky | 3.49| 3.18| _91.1_

| | |Female versus | Male |Female| male | | | (M = 100) ----------------------------------------+------+------+-------------- | (50) | (30) | U. S. whites (miscellaneous) | 3.29 | 2.87 | _87.2_ | (41) | (8) | Negro, full-blood, African and American | 3.54 | 3.14 | [163]_88.7_ |(261) |(191) | Australians | 3.44 | 3.07 | _89.2_

+------+------+---------------

The table shows the Eskimo jaw to be absolutely the highest at the symphysis of all those available for comparison, with the female nearly the highest.[164] Relatively to stature it exceeds decidedly all the groups, the Indians that come nearest matching it in the absolute measurement being all much taller than the Eskimo. And the female Eskimo jaw is relatively high compared with that of the male, being exceeded in this respect only in three of the Indian groups, in two of which, however, the showing is due wholly and in one partly to a lesser height of the male jaw. The relative excess of the female jaw in this respect seems particularly marked in the northern and northeastern groups, though it must remain subject to corroboration by further material.

The white, Negro, and Australian data have an interest of their own.

FOOTNOTES:

[161] Should there be a decided notch in the middle, as happens in rare specimens, it is rational to take the measurement to the side of the notch.

[162] From my Phys. Anthr. of the Lenape, etc., the Anthropology of Florida, and the Catalogue of Crania.

[163] Approximately.

[164] Rudolf Virchow, as far back as 1870, in studying some mandibles of the Greenland Eskimo, found that the height of the body in the middle (3.5 centimeters) was greater than that of the lower jaws of any other racial group available to him for comparison. Archiv. für Anthrop., IV, p. 77, Braunschweig, 1870.

STRENGTH OF THE JAW

The Eskimo jaw is generally stout. Barring rare exceptions there is nothing slender about it. The body, moreover, is frequently strengthened by more or less marked overgrowths of bone lingually below the alveoli and above the mylohyoid ridge. These neoformations will be discussed later.

The strength of the mandible may be measured directly in various locations on the body. Due to the peculiar build of the body, however, and especially to its variations, these measurements are by no means simple and wholly satisfactory. It is hardly necessary in this connection to review the various attempted methods, none of which has become standardized. As a result of experience I prefer since many years to measure the thickness of the body of the jaw at the second molars, and that in such a way that either the molars, if the measurement is taken from above, or the lower border of the jaw if it is taken from below, lies midway between the two branches of the sliding calipers with which the measurement is taken. The two methods (from above or below) give results that are nearly alike. In some cases the one and in others the other is the easier, but wherever the teeth are lost the measurement from below is perhaps preferable. The records obtained on the lower jaws of the western Eskimo and other racial groups are given in the next table.

THICKNESS OF THE BODY OF THE LOWER JAW AT THE SECOND MOLARS IN THE WESTERN ESKIMO AND OTHER GROUPS

+--------------+-------------+--------- | Male | Female | Female +--------------+-------------+versus |Right |Left |Right |Left | male | side | side | side | side |(M = 100) ----------------------------------+--------------+-------------+--------- | (240) | (243) | | | | Western Eskimo millimeters|16.2 16.3|15.1 15.1|_92.9_ | | | | (29) | (28) | | | | Florida Indians do | 16.6 | 15.5 |_93.4_ | | | | (21) | (16) | | | | Louisiana Indians do | 16.3 | 15.3 |_93.9_ | | | | (58) | (47) | | | | Arkansas Indians do | 15.2 | 14.7 |_96.7_ | | | | (40) | (22) | | | | Kentucky Indians do | 14.7 | 14.2 |_96.6_ | | | | (50) | (20) | | | | American whites (misc.) do | 14.5 | 12.8 |_88.3_ ----------------------------------+--------------+-------------+---------

The figures show that the Eskimo jaw is very stout. It is exceeded in thickness only by the jaws of Florida, which in general are the thickest in America, and in males is about equaled, in females very slightly exceeded by those of the prehistoric Indians of Louisiana, who belong to the same Gulf type with the Indians of Florida. The old Arkansas Indians, though closely related to those of Louisiana, show a very perceptibly more slender jaw, particularly in the males; while in an old Kentucky tribe (Green River, C. B. Moore, collector) the jaws are still less strong. The lower jaws of the American whites (dissecting-room material) are slightly less stout than even those of the Indians of Kentucky in the males, and much less so in the females. The interesting sex differences are shown well in the last column of the above table.

BREADTH OF THE RAMI

Still another character that reflects the strength of the lower jaw is the breadth of the rami. The most practicable measurement of this is the breadth minimum at the constriction of the ascending branches. A great breadth of the rami is very striking, as is well known, in the Heidelberg jaw, and the Eskimo have long been known for a marked tendency in the same direction. The measurements of the lower jaws of the western Eskimo show as follows:

LOWER JAWS OF THE WESTERN ESKIMO AND OTHER RACIAL GROUPS: BREADTH MINIMUM OF THE ASCENDING BRANCHES

+---------------+---------------+------------- | | |Female versus | Male | Female | male | | | (M = 100) ----------------------- |----- -+-------+-------+-------+------------- | Right | Left | Right | Left | ---------------------------+-------+-------+-------+-------+------------- | (243) | (240) | (237) | (228) | Western Eskimo centimeters| 3.99 | 4.03 | 3.68 | 3.70 | _92_ | (20) | (20) | (13) | (13) | Florida Indians do | 3.82 | 3.85 | 3.39 | 3.34 | _87.7_ | (21) | (19) | (19) | (16) | Louisiana Indians do | 3.72 | 3.72 | 3.29 | 3.27 | _88.2_ | (62) | (60) | (58) | (61) | Arkansas Indians do | 3.47 | 3.47 | 3.24 | 3.23 | _93.2_ | (42) | (40) | (30) | (29) | Kentucky Indians do | 3.44 | 3.44 | 3.18 | 3.21 | _92.9_ | (50) | (50) | (20) | (20) | United States whites | | | | | (miscellaneous) centimeters| 3.17 | 3.14 | 2.89 | 2.82 | _90.5_ ------------------------------------------------------------------------

The Eskimo jaws, and particularly that of the female (relatively to other females), have the broadest rami. Otherwise the series range themselves in the same order as under the measurement of the stoutness of the body.

OTHER DIMENSIONS

Four other measurements were taken on the jaws, namely the length of the body (on each side); the height of the two rami; the bigonial diameter; and the body-ramus angle. The results of the first three may conveniently be grouped into one table.

ADDITIONAL MEASUREMENTS ON THE LOWER JAW

MALE

+---------------+-----------+---------------+-------- |Length of body,|Length of | Height of |Diameter |each side[165] |body as a | ramus[167] |bigonial +-------+-------+whole[166] +-------+-------+[168] | Right | Left | | Right | Left | -----------------+-------+-------+-----------+-------+-------+-------- | (236) (236) | (100) | (132) (131) | (201) Western Eskimo | 10.28 10.28 | 8.03 | 6.45 6.38 | 11.42 | | (24) | (18) | (22) Florida Indian | | 8.45 | 6.72 | 10.75 | | (19) | (15) | (17) Louisiana Indian | | 8.44 | 7 | 10.67 | | (62) | (52) | (57) Arkansas Indian | | 7.88 | 6.52 | 10.49 | | (42) | (37) | (38) Kentucky Indian | | 7.45 | 6.48 | 10.48 U. S. whites | | (50) | (50) | (50) (miscellaneous)| | 7.57 | 6.53 | 10.11 -----------------+---------------+-----------+---------------+--------

FEMALE

+---------------+-----------+---------------+-------- | (230) (228) | (100) | (134) (128) | (199) Western Eskimo | 9.61 9.60 | 7.47 | 5.61 5.57 | 10.57 | | (19) | (18) | (17) Florida Indian | | 7.72 | 6.02 | 9.70 | | (16) | (15) | (15) Louisiana Indian | | 7.38 | 5.77 | 9.90 | | (57) | (52) | (56) Arkansas Indian | | 7.46 | 5.85 | 9.58 | | (30) | (25) | (30) Kentucky Indian | | 7.12 | 5.64 | 9.45 U. S. whites | | (20) | (20) | (20) (miscellaneous)| | 7.02 | 5.87 | 9.12 -----------------+---------------+-----------+---------------+--------

FEMALES TO MALES (M = 100)

+--------+--------+--------+--------- | Length | Length | Height | Diameter | each | as a |of rami | bigonial | side | whole | | -----------------------------+--------+--------+--------+--------- Western Eskimo | _93.4_ | _93.0_ | _87.3_ | _92.6_ | | | | Florida Indian | | _91.4_ | _89.6_ | _90.2_ | | | | Louisiana Indian | | _87.4_ | _82.4_ | _92.8_ | | | | Arkansas Indian | | _94.6_ | _89.7_ | _91.3_ | | | | Kentucky Indian | | _95.6_ | _87.0_ | _90.2_ | | | | U. S. whites (miscellaneous) | | _92.7_ | _89.9_ | _90.2_ -----------------------------+--------+--------+--------+---------

The Eskimo lower jaw, which, as seen before, is characterized by a high and stout body and the broadest rami, shows further that these rami are remarkably low, and that the bigonial spread is extraordinarily broad. The length of the body, on the other hand, is not very exceptional, being perceptibly exceeded in some of the Indians.

FOOTNOTES:

[165] Sliding calipers: Separate measurement of each half of the body, from the lowest point on the posterior border of each ramus not affected by the angle to a point of corresponding height on the line of the symphysis. The anterior point may, in consequence of a lower or higher location of the posterior point, range from the chin to above the middle of the symphysis, but the results are much alike. The measurement leaves much to be desired, but is the best possible if the two halves of the body are to be measured separately.

[166] The length of the whole jaw is measured on Broca's mandibular goniometer, by laying the jaw firmly on the board, applying the movable plane to both rami, and recording the distance of the most anterior point of the chin from the base of the oblique plane. This measurement is easier than the previous, though on account of the variation in the angles and the lower part of the posterior border of the rami it is also not fully satisfactory, and it does not show the differences in the two halves of the body.

[167] Sliding calipers: One branch applied so that it touches the highest points on both the condyle and the coronoid, while the other is applied to the lowest point of the ramus anterior to the angle, if the bone here is prominent; if receding, the branch of the compass is applied to the midpoint on the lower border of the ramus.

[168] Sliding calipers: Maximum external diameter at the angles; the maximum points may, exceptionally, be either anterior to or a little above the angle proper.

THE ANGLE

The angle between the body and the ramus of the lower jaw is known to differ with the age and sex as well as individually. Not seldom it differs also, and that sometimes quite appreciably, on the two sides. Racial differences are as yet uncertain.

The angle, especially in some specimens, is not easy to measure, and the position of the jaw may make a difference of several degrees. Numerous trials have shown that the proper way is to measure the angle on the two sides separately, and to so place the jaw in each case that there is no interference with the measurement by either the posterior or the anterior enlarged end of the condyle.

Leaving out jaws in which extensive loss of teeth has in all probability resulted in changes in the angle, the western Eskimo material gives the following data:

WESTERN ESKIMO: ANGLE OF THE LOWER JAW

+-------+-------++----------+-------+------- | Male | Female|| | Male | Female -----------+-------+-------++----------+-------+------- | (224) | (217) || | (218) | (207) Right side | 119.6°| 124.5°||Left side | 119.5°| 124.3° -----------+-------+-------++----------+-------+-------

In the male Munsee Indians the angle was 118°; in those of Arkansas and Louisiana, 118.5°; in those of Peru (Martin, Lehrb., 884), 119°. In the whites, males, the average angle approximates 122°; in the Negro, 121° (Topinard, Martin).

The angle in the female in the Eskimo is to that of the male as 104 to 100; in the Arkansas and Louisiana series it was 103. In the whites the proportion seems to be a little higher.

There are evidently, if we exclude the whites in whom the shortness of the jaw conduces probably to a wider angle, no marked racial differences, but the subject needs a more thorough study on large series of sexually well-identified specimens, carefully selected as to age.

The average angle on the right differs in the Eskimo but very slightly from that on the left, though individually there are frequent unequalities.

RÉSUMÉ