12 



HEREDITY 



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distribution of the variation among the population 

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52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 6 



Stature in Inches 



70 71 72 73 74 75 76 77 7S 79 



Fig. 2. Curves showing distribution of stature in women (mothers) 

 — dotted line ; and in men (fathers) — continuous line. The curves 

 approach the ' normal curve.' (Data from Pearson.) 



variable character is classified, the more nearly the 

 line joining the tops of the ordinates will approxi- 

 mate to a smooth curve ; e.g. if the population were 

 measured to the nearest quarter of an inch instead 

 of to the nearest inch there would be four times 



