CHAPTER IV. 



The Head. 



TJlc Length of the Head. 



The average length of the head, measured with the caHpers 

 from the glabella to the most distant point on the occiput, was 

 found to be i88 mm., or 1 1.43 percent of the body-height. The 

 range of extreme individual variation extended from 169, the 

 shortest, to 208 mm., the longest head, a difference of 39 mm. 

 or 20.74 percent of the average length of the head. This is much 

 smaller than the range of individual extreme variation observed 

 in the case of stature (3 1 percent). This confirms the ac- 

 cepted dictum that the head is by far less variable than the height 

 of the body, probably because it is less, or not at all, exposed to 

 the influence of external conditions such as climate, nourishment 

 and social status. 



Table XVI. 



Length of the Head, 1,528 Men. 



Length of the 



Number. 



Percent. 



Length of the 



Number. 



Percent. 



Head (in mm.) 







Head {in mm ). 







169-170 



4 



0.26 



I9I-I92 



186 



12.18 



17I-172 



5 



0.36 



193-194 



122 



7.98 



173-174 



10 



0.65 



195-196 



92 



6.02 



175-176 



20 



1-31 



197-198 



62 



4.06 



177-178 



34 



2.22 



199-200 



zz 



2.16 



179-180 



90 



5-89 



201-202 



23 



I-5I 



181-182 



105 



6.87 



203-204 



7 



0.46 



183-184 



136 



8.90 



205-206 



10 



0.65 



185-186 



204 



1335 



207-208 



2 



0.13 



187-188 

 189-190 



181 

 202 



11.85 

 13.22 











1,528 



100.03 



The standard deviation was calculated to be 6.129, ^^'^^ the 

 probable error 0.105, both of which are nearly the same as was 

 found for stature. The range of individual variation is shown in 

 the accompanying table (XVI) giving the seriation of the length 

 of the head at intervals of two millimeters. The curve drawn 



207 



