394 



THE GRAMMAR OF SCIENCE 



the mode of the second depends upon the number of 

 stigmatic bands on the first ; it is not as low as the first, 

 but differs from it in the direction of the mode (lo) of the 

 general population of poppies. 



Similarly if I take out all pairs of capsules which have 

 one member with 1 3 bands, we have :— 



The mode is now 12, and has departed from 10 in 

 the direction of i 3. This is the phenomenon of regression, 

 namely, that in associated or correlated pairs, if we select 

 one member with a given value for its character, the 

 second has on the average a less value, regressing some- 

 what to the mean of the general population. Here, of 

 course, regression will stand for progression, if the selected 

 member has less of the character than the average 

 population. 



The following table — a so-called correlation table — - 

 will now be intelligible. 



If we take any column, say the 9 column, we have a 

 distribution of frequency under it corresponding to the 

 frequency with which capsules of 6, 7, 8, etc., bands were 



