INHERITANCE OF HTBIAN CHARACTERS 521 



122 sucTi matings producing 371 children, 193 were found to be feeble- 

 minded, 178 normal, which is remarkably close to expectation con- 

 sidering the difficulty of determining with certainty the real character 

 of the parents. When two individuals of the NF type mate, their 

 offspring would be expected to give 3 normals to i feeble-minded. 

 Out of 146 children produced by 33 such matings Goddard found 39 

 were feeble-minded. 



The first of Goddard's charts (Fig. 96) illustrates the family tree 

 of Gertie K., a girl of 12 years, with the mental development of a child 

 of 7. Males in this and the following chart are represented by squares, 

 females by circles. Note that this girl has a feeble-minded brother 

 and that both her parents are feeble-minded and see the appalling 

 array of feeble-minded cousins, aunts, uncles, and other relatives. 

 Her grandmother passed for a normal individual, although it would 

 seem from her children she must have been an NF individual. The 



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O 



00 ■-•• m ® D 



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Gisntl* 



Fig. 96. — Pedigree showing heredity of feeble-mindedness: family of Gertie K. 

 (From Downing, after Goddard.) 



second chart (Fig. 97) is quite exactly Mendelian, if we suppose the 



grandparents were NF individuals. This case is particularly interest- 

 ing, for the parents of these six feeble-minded children were high-grade 

 morons, both immigrants. The pubhc must support the children 

 because we have as yet instituted no expert examinations to detect 

 such defectives among our immigrants in order to refuse them admis- 

 sion to this country. 



See what a single unfortunate alliance can produce. A young 

 man to whom Goddard gives the fictitious name of Martin Kallikak 

 had children by a feeble-minded girl in the days before the Civil War. 

 There have been traced some 480 descendants from this mating, and 

 all of them are below normal intelligence. Later this same man 

 married a good Quaker girl, and 496 of the descendants of this marriage 

 have been traced, all of normal mentahty. The contrast is strikingly 

 instructive, for the conditions are almost those demanded by a scien- 

 tific demon station. 



