298 SECRETS OF ANIMAL LIFE 



appearance; there is a clear hereditary factor in 

 licentiousness; pauperism indicates bodily or 

 mental weakness, and the latter is linked with 

 criminality; penal institutions have little beneficial 

 influence upon persons of defective mentality; 

 one in four Jukes is improved socially by Children's 

 Institutions; a change of environment gives the 

 individual a new opportunity and a chance of 

 mating into better families. In many cases, how- 

 ever, the ne'er-do-well in new surroundings finds 

 another like himself. Improved social environment 

 demonstrably counts for much in the individual's 

 development, but this depends on the response 

 that he is able and willing to make, and the power 

 of response depends on the hereditary constitution. 

 Yet " heredity, whether good or bad, has its comple- 

 mental factor in environment." 



Mr. Dugdale laid emphasis, as we have said, on 

 the deteriorative effect of continuous bad surround- 

 ings; Dr. Estabrook's study, carefully documented 

 with genealogical trees, shows that the hereditary 

 factor is in some cases equally important, e.g., as 

 regards weak-mindedness. It is probably unjust to 

 trace all the innate deficiencies of later date to the 

 original Juke strain, since evils bred in the bone 

 would be sometimes accentuated by mating with 

 similarly disposed members of other stocks. As to 

 weaknesses that can be classed as Mendelian unit- 

 characters a question very partially answered, 

 it must be noted that outbreeding with normal 

 members of the community would affect the dis- 



