Social Environment and Eugenics T05 



It is, of course, dear that density of popu- 

 lation in itself is not the true cause sought; but 

 rather, if the cause is environmental, it must 

 consist of certain influences associated there- 

 with. Density undoubtedly means the presence 

 of cities, and cities mean, in turn, many eco- 

 nomic and cultural influences. It is worth 

 while, then, to compare rank in urban popu- 

 lation and in noted men. It was not found 

 convenient to rank the states for the percentage 

 of urban population in i860, as the figures 

 were not available; but those for 1890 were 

 obtained and were correlated with fertility in 

 noted men as measured on the basis of the cen- 

 sus of 1880. The coefficient was found to be 

 0.82 ± 0.04. The height of the measure in 

 spite of the handicap of later censuses indicates 

 the importance of the city environment, inas- 

 much as density of population taken alone may 

 in some instances mean thickly settled rural 

 districts. Another proof of the importance of 

 cities may be set forth. The states have been 

 ranked in accordance with the amount of man- 

 ufacturing to the square mile, and this ranking 

 has been correlated with fertility in noted men 

 — both on the basis of the census of i860. 

 The result is a coefficient of 0.89 ± 0.03 for 



