818 



MEMOIRS NATIONAL ACADEMY OF SCIENCES. 



[Vol. XV, 



Here there seems to be an increase, if anything. In a corresponding report from Camp 

 Upton on 600 negro enlisted men there is a definite increase: 



These data are, however, scanty and quite possibly reflect in every case different principles 

 of selection at work within the Army. At best we can say that a general trend for officers 

 throughout the entire range is made out, but that this trend with officers or enlisted men may 

 not be definite within the decade of the draft ages. 



The distribution of ages for officers within the various branches of the service is interesting 

 as affecting the comparison of these branches. Table 372 shows these distributions. Most 

 frequently the medians fall in 27-28 group, where is the median for the group of officers taken 

 as a whole (28.8). The Artillery officers are a little younger than the rest. The officers of 

 the Field Signal battalions and of the Quartermaster Corps are slightly older. Officers in the 

 Medical Corps are very much older. The median for this corps falls at 37.6 years, and more 

 than tliree-quarters of the group are over 30 years old and slightly more than one-third over 

 40 years. This fact is of special interest in connection with the low rating of medical officers 

 (see chap. 16). In the total group of officers a little more than one-third (38 per cent) are over 

 30 years of age. 



Table 372. — Age distribution of officers. Figures are percentile distributions for different arms of the service. 



Age group (years). 



20 and 



29-30 



31-40 



41-50 



51-60 



Median 



Number 

 of cases. 



Infantry 



Artillery 



Machine-gun battalions. 



Engineers 



Field Signal Corps 



Quartermaster Corps 



Medical Corps 



Dental Corps 



Veterinary Corps 



All officers 



0.3 

 .1 



11.3 

 10.6 

 6.7 

 5.5 

 4.0 



3.9 

 3.2 



6.4 



19.8 

 23.4 

 21.2 

 16.9 

 14.7 

 13.2 

 2.2 

 16.8 

 13.6 

 15.2 



19.7 

 20.4 

 18.9 

 17.2 

 16.4 

 15.4 

 4.8 

 25.0 

 18.7 

 15.9 



15. 1 

 15.6 

 16.2 

 18.0 

 13.2 

 16.6 

 7.3 

 16.8 

 22.0 

 13.8 



11.1 

 12.2 



8.5 

 12.2 

 13.5 

 12.4 



8.1 

 14.2 

 15.1 

 10.9 



20.0 

 15.3 

 19.9 

 25.6 

 27.9 

 25.0 

 42.0 

 17.2 

 26.7 

 25.8 



4.7 

 1.7 

 4.7 

 4.5 

 8.6 

 11.9 

 30.1 

 6.0 

 2.4 

 10.6 



.5 



.3 



1.1 



5.6 



.4 

 .1 



27.2 

 26.5 

 26.9 

 28.1 

 29.0 

 29.1 

 37.6 

 27.5 

 28.5 

 28.8 



6,842 



1,507 



493 



984 



350 



747 



3,090 



413 



251 



15,385 



