Karl Pearson 275 
Curve III. Curve of Fertility of Individual Parentages of first generation : 
_ 1 / .r-G-0526g- i\- 
y=1e 2 V 5-6560(ri ; . 
(N.B. Only one half of this curve is drawn.) 
Curve IV. Distribution of Effective Parentages in first generation : 
V27r 1-49480-, 
Curve V. Distribution of Males in second generation : 
\/27r -OSSlo-, 
