

FRETS, THE INDEX CEPHALICUS. 511 
2. THE INDEX CEPHALICUS. 
JOHANNSEN (1907) has criticized the use by anthropologists of 
the headindex. He came to it by the study of variability from the 
shape of beans in pure lines. JOHANNSEN remarks, that the index 
of long heads is relatively lower than that of short heads and con- 
cludes that the indices may not be compared with each other 
without a correction. For the Swedish material of RETZIUS and 
First he gives an application of this consideration. 
Before JOHANNSEN, Boas had already found (1899) from a 
material of 239 Sioux Indians, that the heads which have absolutely 
the greatest lengths, have the lowest indices (p. 449). And JENNINGS 
(1908) finds in Paramecium (p. 501—503) that the index of length and 
breadth is in general smaller for large lengths than for small lengths. 
I have made this inquiry for my material. Out of the tables 4 
and 5 that give the headbreadth, the headlength and the indices 
for 935 adult men and for 1426 adult women (p. 494) are com- 
posed the tab. 14 and 15 (p. 512) that show how many cases of 
each index occur for different classes of headlength and of head- 
breadth. For each lengthclass and breadthclass the mean and the 
standarddeviation are calculated. It appears that for the male as 
well as for the female with a larger headlength the index decreases. 
For breadthclasses, with a larger headbreadth the index increases. 
For the same lengthclass women are more dolichocephalic than 
men; and for the same breadthclass more brachycephalic. As for 
the standarddeviation, we find that in general the standarddeviation 
for high indices is a little larger than for low indices. This 
interesting fact has found its explanation in another part of this 
investigation. 1) 
I have made these calculations also for the material of TOCHER 
(1906). TocHER gives for the headlength and the headbreadth of . 
4436 male and 3951 female inmates of Scottish asylums similar 
tables as my tables 4 and 5; the indices are however not mentioned. 
I have inserted in these tables for headlength and headbreadth 
the indices and then composed the tables 16 and 17 (p. 514-7). We 
see a similar result as in the tables 14 and 15 from my material, 
1) See Genetica III, p. 193—390; also separately MARTINUS NIJHOFF, 
the Hague 1921. 
