96 NATURAL INHERITANCE. [CHAP.

the Table so far as it now concerns us. The horizontal dotted lines and the graduations at their sides, correspond to the similarly placed lines of figures and graduations in Table 11. The dot on each line shows the point where its M falls. The value of its M is to be read on the graduations along the top, and is the same as that which is given in the last column of Table 11. It will be perceived that the line drawn

FIG.10.

ed 6s .'0

through the centres of the dots, admits of being interpreted by the straight line C D, with but a small amount of give and take ; and the fairness of this interpretation is confirmed by a study of the MS. chart above mentioned, in which the individual observations were plotted in their right places.

Now if we draw a line A B through every point where the graduations along the top of Fig. 10, are the same as those along the sides, the line will be straight and will run diagonally. It represents what the Mid-

72

84

iC 6s 66 6y

a | |

--REGRESSION FROM '-MID-PARENT TO-SON ---------- |
'PARENT ------- |