THE APPLICATION TO MAN 



235 



and our 100,000 paupers in almshouses and out " 

 (Davenport). 



7. THE CONTROL OF DEFECTS 



The method of possible control of human defects 

 depends upon whether they are positive or negative, 

 that is, dominant or recessive. In those cases where 

 a given defect is due to a single determiner the 

 Mendelian expectation for the possible offspring 

 arising from various matings is indicated in the fol- 

 lowing table in which D stands for the defect and d 

 for its absence : 



THE MENDELIAN EXPECTATION FOR DEFECTS 



If the defect is positive and in a duplex or homo- 

 zygous condition in one parent, as in 1, 2, and 4 

 above, all the offspring will possess it regardless of 

 the germinal constitution of the other parent. In 



