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206   NATURAL INHERITANCE.

TABLE 9.
MARRIAGE SELECTION IN RESPRCT TO STATURE.

The 205 male parents and the 205 female parents are each divided into three groups-T, M, and S, and t, m, and s, respectively=that is, Tall, Medium, and Short (medium male measurements being taken as 67 inches, and upwards to 70 inches). The number of marriages in each possible combination between them were then counted, with the result that men and women of contrasted heights, Short and Tall, or Tall and Short, married about as frequently as men and women of similar heights, both Tall or both Short; there were 32 cases of the one to 27 of the other.

 

S., t.

12 cases.

M., t.

20 cases.

T., t.

18 cases.

S., m.

25 cases.

M., m.

51 cases.

T., in.

28 cases.

S., s.

9 Cases.

M., S.

28 cases.

T., s.

14 cases.

Short and tall, 12 + 14 = 32 cases.

Short and short, 9l = 27 cases. Tall and tall, l   J8

We may therefore regard the married folk as couples picked out of the general population at haphazard when applying the law of probabilities to heredity of stature.

TABLE 9A.
MARRIAGE SELECTION IN RESPECT To EYE-COLOUR
in 78 Parental Couples.

 

Eye Colour of

No, of

cases

Per Cents.

-

Eye Colour

of Husband

and Wife.

Husband

Wife.

observed.

Obs.

Chance.

Observed.

Chance.

Light

Light

29

37

37

     

Hazel

Hazel

2

3

2

48

46

Alike

Dark

Dark

6

8

7

     

Light

Hazel

Hazel

Light

18

23

15

28

22

on

Hazel

Dark

         

traste

rasted

Dark

Hazel

i   4

5

7

     

Light

Dark

19

24

32

24

32

Contrasted

Dark

Light

           

The chance combinations in pairs are calculated for a population containing 61.2 per cent, of Light Eye-colour, 12.7 of Hazel, and 26 .1 of Dark.