NOTICES AND BIBLIOGEAPHY. 
NOTICES*. 
Untersuchungen iiber das Verhdltms der Kopfmasse zu den Schddelmassen, by 
Jan Czekanowski. Braunschweig, 1907. 
An interesting paper giving between 30 and 40 measurements, indices, etc., of each of 
119 specimens (65 (J and 54 $) and the treatment of the observations. The calculations 
of the mean, median, average deviation, standard deviation, coefficient of variation and coefficient 
of correlation are explained. The method of moments is referred to, but the tnth moment 
m/l n „i 
IS given as W - 2 , where Ck is the deviation and n the number of cases. An explanation 
* K = l 
of the measurements is given and various tables giving means etc. follow. Formulae are given 
for the calculation of skull from head measurements. Amongst other interesting points the 
author refers to the variation of the thickness of the skin with the age of the individual at 
various parts of the head. Czekanowski does not appear to have read any of the very recent 
1 - 
English statistical papers and he gives -67449 as the probable error of r, while in some 
Vw (l+r) 
of his correlations there is probably spurious correlation, e.g. the table on p. 28 which gives the 
correlation between the cephalic indices of the head and skull measurements. 
Zur Frage der Correlation en der Muskelvarietaten, by Jan Czekanowski. New 
York, 1906 (Boas Memorial Volume). 
Certain muscles are not always i)resent, and this paper gives the frequency of the presence 
of thirteen muscles and the coefficients of correlation between the various muscles. The number 
of cases investigated is not large and the coefficients vary considerably. The subject would 
be well worth an extended investigation on the same lines. 
The Numerical Proportions of the Sexes at Birth, by J. B. Nichols. American 
Anthropological Association, Lancaster, Pa. U.S.A. 1907. 
Statistics from Europe, United States, South America, Australia, etc. are used, and the points 
dealt with are the proportions of births among living and still-born, among legitimate and 
illegitimate ; multiple births ; effect of war on sex ratios ; differences between ratios in town 
and country and influence of sanitary environment. A valuable collection of stati-stics which 
would have been improved if an estimate of the probable errors had been given in each case. 
* Authors of memoirs who desire brief notices of their contents should forward offprints to this 
Joumal, as it is often difficult to procure Journals in which the originals have been issued. 
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