J.—PSYCHOLOGY. 229 
children, that the average level of inborn intelligence among adults 
aged twenty to fifty is but little above that of children of fourteen, and 
that the distribution of intelligence, among adults as among children, 
approaches pretty closely to the so-called ‘ normal curve.’ (See fig. 1, 
which shows the distribution of marks in the intelligence-tests set at 
the last Civil Service examination—Clerical Class, 1922.) 
DISTRIBUTION OF INTELLIGENCE. 
8599 ADULTS. 
NUMBER OF ‘ivil Service Exami ion—. 999 ) 
Re OF (Civil Service Examination—July 1922.) 
1300 
1200 
00 
400 
300 
200 
0 0 2 30 40 930 60 70 80 90 10 NO 120 130 140 150 160 170 180 190 200 
Scale of Marks. 
Fie. 1. 
