152 HEREDITY AND EUGENICS 



condition of primitive man. Goddart cites a family 

 of eleven feebleminded children from two white feeble- 

 minded parents. There were also two " normal " 

 children, but they were black. The mentality of 

 the negro is distinct from that of the feebleminded. 

 The latter presumably occur also in primitive races. 

 The evidence, so far as it goes, also appears to indi- 

 cate the gradual evolution of the mentality of normal 

 civilised man, involving man}' steps, whatever may 

 have been the forces involved. 



Holmes points out that where a normal person 

 married to a feebleminded one has some feebleminded 

 children, it is too easily assumed that the normal 

 parent was heteroz3^gous for this defect. If this were 

 always true, it would give a ver}- high frequency for 

 the occurrence of this latent defect (see p. 159). It 

 seems much more likely, as Holmes points out, that 

 the normal mentalit}^ show^s variable or incomplete 

 dominance, especially when, as is usual in such 

 matings, the normal parent is also intellectually 

 below par. 



Goddart estimated the number of feebleminded 

 in the United States at 300,000 to 400,000. He 

 thinks it important that the public should understand 

 the mentality of a moron (mental age ten), and employ 

 him accordingl}', recognising his limitations. The 

 moron has a lifetime in which to learn to do efficiently 

 things that can be done by a boy of ten. Goddart 

 suggests that their training should be carefully 

 arranged according to mental age tests, that as many 

 as possible should be " colonised," some sterilised, but 

 the great mass " educated " for their proper work. 



The *' Mongolian " is a well-defined type of mental 

 defectiveness, which has generall}' been regarded as 

 non-inherited. The oblique eyes and round faces of 

 Asiatics are combined wath short stubb}' fingers, 

 rather dry rough skin, poor circulation, lack of 



