32 THE TREND OF THE RACE 



of pauperism, alcoholism, harlotry and frequently graver forms 

 of crime. 



Several investigators have drawn the conclusion that feeble- 

 mindedness, which is an inherited trait in probably four-fifths of 

 the cases, is transmitted as a recessive or partially recessive 

 character, although it is not so evident that it behaves as a single 

 unit in inheritance. Feeble-minded children sometimes come 

 from normal parents, both of whom, however, may have been 

 heterozygous for feeble-mindedness. Such children frequently 

 result from the mating of a feeble-minded person with a normal 

 individual, but when both parents are feeble-minded we find that 

 in nearly all cases all the children are feeble-minded, as we should 

 expect. The few recorded exceptions to this rule may be due to 

 illegitimacy which is a not infrequent occurrence among this 

 class, or to mistaken judgment of the parents' or the child's men- 

 tal condition, or the fact that one parent may have been feeble- 

 minded through accident or disease. Out of 41 matings in the 

 Kallikak family in which both parents were feeble-minded there 

 were 222 feeble-minded children and only two others that were 

 considered normal. In his work on Feeble-mindedness Goddard 

 states that of 482 children both of whose parents were feeble- 

 minded all but six were reported to be feeble-minded also. 



The conclusion of Goddard that only mentally defective 

 children are to be expected from two mentally defective parents 

 which was announced by Davenport in 191 1 as "the first law of 

 inheritance of mental ability" was materially modified in a paper 

 on the Hill Folk published by Danielson and Davenport in 191 2. 

 "The analysis of the data," according to the authors, "gives 

 statistical support to the conclusion abundantly justified from 

 numerous other considerations, that feeble-mindedness is no ele- 

 mentary trait, but is a legal or sociological, rather than a biologi- 

 cal term. Feeble-mindedness is due to the absence, now of one 

 set of traits, now of quite a different set. Only when both parents 

 lack one or more of the same traits do the children all lack the 

 traits. So, if the traits lacking in both parenrs are socially impor- 

 tant the children all lack socially important traits, i. c, are feeble- 



