FRETS, THE INDEX CEPHALICUS. 499 







Table 9. 
NUMBER INDEX 
AGE oe : 
M F | M F 
Gen 145 141 80.96 | 81.55 
sn 159 125 80.82 | 814 
10 14 158 153 81.26 | 80.64 
15—19 131 159 80.6 81.1 
2024 101 169 79.76 | 80.94 
2s NIG ETEN 51 79.65 | 80.6 
0—19 593 578 80.9 81.22 
20201 QE 1463 79.65 | 80.64 
Oe 1545 2057 80.4 81.04 



are slight and irregular and the numbers small,1) but when we 
group the material as in tab. 9, it appears, that with advancing 
age (0—20 years) the index slightly falls. Also it appears from 
tab. 8, that the growth of the head continues to about the twenty- 
fifth year (see also QUETELET 1875, DENIKER 1900, p. 31 and: 
PFITZNER 1901). ScHUSTER (1911, p. 48 and tab. 1) finds from head- 
measurements with 957 English students of 18—26 years, that there 
is some indication that the length increases during the period 
dealt with. The mean headlength at 18 is 195.2 m.m., at 21 196.05 and 
at 27 197.4 m.m. The breadths for these years are 152.9, 152.7 and 
153.1 m.m. respectively, so that this measurement shows little if 
any increase. 
For the index of the adults of my material (tab. 1) I find for 
962 men aging 20 years and more M = 79.65 and os — + 2.985 and 
for 1463 women of the same ages (tab. 1) M = 80.64 and c = + 2.815. 
So, comparing the mean indices of the whole material, of the 
adults and of the children (tab. 9), it is clear that in my material 
the index of children is a little higher than that of adults. 
RETZIUS and Furst found for the mean index of 45000 recruits 
M = 75.855, I calculated M + o = 76.122 + 3.082. I found for 962 
adult men M + s = 79.65 + 2.985, When we take into consideration, 
to compare my material with the Swedish, that the index of my 
1) For each age the variability of headlength, headbreadth and index is 
very large, but the number of observations is too small, to express it in the 
standarddeviation. 
