EUTHEXICS AXD EUGENICS 17 



will apply his intelligence to the bettering of his condition'*' (p. 26). 

 " Why are men and women so apathetic over the prevalence of disease? 

 "Why do they not devote their energies to stamping it ont? For no 

 other reason than their disbelief in the teachings of science, coupled 

 with a lingering superstition that, after all, it is fate, not will power, 

 which rules the destinies of mankind"" (p. 28). "There is no greater 

 evil than the congestion of streets and buildings "' (p. 48). 



In apparent contrast to the euthenics view of the importance of 

 conditions is the eugenics view of the importance of blood. Taking 

 an extreme case, a child is born an imbecile and neither the best of nutri- 

 tion, the most scrupulous cleanliness, the purest air and sunshine, nor 

 the best of physical and mental training will make anything else out 

 of him. Imbecility can not be cured; in most of its forms it is a 

 necessary result of the nature of the parental mating. It is a defect 

 due to a patent or latent defect in both of the paternal germ plasms. 

 The imbecile is an imbecile for the same reason that a blue-eyed person 

 is blue-eyed. 



Lest you have not heard where a blue-eyed child gets its eye color, 

 let me recount the story. Brown eyes are due to a brown pigment 

 laid down in the iris; blue eyes are due to a lack of such pigment. 

 "When both parents are brown-eyed the children get the tendency to 

 form iris pigment from both sides of the house, and the condition of 

 the pigment is said to be duplex. If the children get the tendency 

 from one parent only, they still have brown eyes, but the condition is 

 said to be simplex. If both of the parents lack brown eye-pigment, 

 that is proof that the power of producing it is absent from their germ 

 cells. Xow, what is absent from the germ cells can not be transmitted, 

 consequently, two parents lacking brown in the iris (blue-eyed) will 

 never have children with brown eyes, but only with blue eyes. If both 

 parent* have brown eyes simplex, then one in four of the children will 

 have blue eyes. If one parent has simplex brown eyes and the other 

 has blue eyes, one half of the children will have blue eyes. But, if 

 in both or either one of the parents the brown iris pigmentation is 

 duplex all of the offspring will have brown eyes. 1 



Table of Matlxgs avd Offspblsg — Ete Color 



All with pigmented iris (brown-eyed). 

 All pigmented, but half simplex. 

 All pigmented and all simplex. 

 i duplex pigmented; i simplex; i un- 



pigmented (blue-eyed). 

 i simplex; i unpigmented (blue-eyed). 

 All unpigmented (blue-eyed). 



1 These different ca-ses of inheritance fall into six groups as in the following 

 table, in which PP stands for duplex pigmentation, Pp for simplex pigmentation 

 and pp for lack of pigmentation. 



vol. lxxviii. — 2 



One Parent 

 PP 



Other Parent Ofispririff 



PP PP.. PP. 



PP 



Pp PP, Pp. 



PP 



pp Pp, Pp. 



PP 



Pp PP, Pp, pP, pp. 



Pp 



PP PP, PP- 



PP 



PP PP- PP- 



