The curvature of the sacrum in the Munsee can be described in 18 of the
20 specimens as medium, while in two (one male and one female) it is
submedium. This agrees closely with the author’s observations on this
feature in other Indians. In the United States whites the proportion
of regular and medium forms is smaller, while not infrequently there
exists in the sacrum of whites a pronounced curvature, which is very
rare in the Indian. Among 115 Indian sacra from Arkansas, Louisiana,
the Southwest, and Mexico, the writer found moderate or medium
curvature in 75, or 65 per cent; submedium to slight in 24, or 21
per cent; and pronounced (though never excessively) in 16, or 14 per
cent. Among the 217 specimens examined by Emmons, moderate or medium
curvature was present in 148, or a little more than 67 per cent;
submedium in 52, or 24 per cent; and pronounced in 18, or 8 per cent.
[Illustration: BUREAU OF AMERICAN ETHNOLOGY BULLETIN 62 PLATE 27
FEMALE MUNSEE SACRUM SHOWING UNILATERAL ARTICULATION WITH THE LAST
FIFTH LUMBAR]
The curve of the sacrum begins in the Munsee (and the same is true of
other Indians) in a majority of cases with the first or upper-most
segment, but in numerous instances with the second vertebra. More in
detail, among the 20 Munsee sacra, in 13, or 65 per cent, the curve
began with the first; in six, or 30 per cent, with the second; and
in one, or 5 per cent of the cases, with the third vertebra. Among
113 sacra of both sexes from Arkansas, Louisiana, the Southwest, and
Mexico, examined by the writer, the curve began in 52, or 46 per cent
of the cases, with the first; in 42, or 37 per cent, with the second;
in 14, or 12 per cent, with the third; and in five, or 4 per cent, with
the fourth vertebra. In the female series studied by Emmons, the curve
began in 41.5 per cent of the cases with the first; in 27 per cent with
the second; in 22.5 per cent with the third; in 7.4 per cent with the
fourth; and in 1.8 per cent with the fifth segment. Among whites, in
224 sacra of five segments examined by the writer, the curve began with
the first vertebra in 87 per cent; with the second in 5.4 per cent; and
with the third in 7.6 per cent of the cases. It is therefore evident
that the anterior curve of the sacrum begins more frequently higher
up in the whites than in the Indians. This peculiarity is probably
connected with a somewhat greater curvature, even on the average, in
the sacrum of whites.