29^ Heredity and Eugenics 



kill, Taconic, and Adirondack masses show many endoga- 

 mous centers. In one place a race of criminals is being 

 formed; in another a feeble-minded strain; in another an 

 albino race, and so on. There is reason for thinking that 

 the \-alleys of eastern Kentucky and Tennessee are centers 

 of inbreeding and nearly pure races are being formed there. 

 In larger settled countries the process has gone farther. 

 From the Chin Hills, Burmah, one hears: "Rau Vau Village 

 has been isolated for about seven generations. It contains 

 about sixty houses and possibly two hundred inhabitants. 

 Of these ten are idiots, many are dwarfs, and some hydro- 

 cephalic. A number of cases of syndactylism or webbing 

 of hands, and brachydactyly occur." 



Only slightly less important than the geographical barriers 

 are the social. A public institution brings together men and 

 women so intimately that marriages frequently occur after 

 lea^'ing the institution. Thus two persons with the same 

 trait become parents. Almshouses in which segregation of 

 the sexes is imperfect yield numerous depauperate and 

 imbecile offspring, and there is reason for suspecting that 

 sanatoria and some hospitals for the "curable" insane 

 lead to marriage of two weak persons. That institutions 

 for the deaf lead to the marriage of similarly defective 

 is notorious. Thus Dr. Bell, who has long warned us of 

 the imminent danger of the formation of a deaf variety 

 of the human race in America, says: "I desire to direct 

 attention to the fact that, in this country deaf mutes marry 

 deaf mutes. An examination of the records of some of our 

 institutions for the deaf and dumb reveals the fact that 

 such marriages are not the exception but the rule." 



The barrier of language is extremely important in pro- 

 moting consanguineous marriages, or the matings of persons 



