408 Dr. F. Galton. The average Contribution of each 



tives of the normal condition. I have not unravelled the causes 

 of this error, and it is not urgent to do so, since its ill effects are 

 swamped by the large number of successes elsewhere. 



In order to satisfy myself that the correspondence between calcu- 

 lated and observed values was a sharp test of the correctness of the 

 coefficients, I made many experiments by altering them slightly, 

 and recalculating. In every case there was a notable diminution in 

 the accuracy of the results. The test that the theory has success- 

 fully undergone appeared on that account, to be even more searching 

 and severe than I had anticipated. 



It is hardly necessary to insist on the importance of possessing a 

 correct law of heredity. Yast sums of money are spent in rearing 

 pedigree stock of the most varied kinds, as horses, cattle, sheep, pigs, 

 dogs, and other animals, besides flowers and fruits. The current 

 views of breeders and horticulturists on heredity are contradictory in 

 important respects, and therefore mud be more or less erroneous. 

 Certainly no popular view at all resembles that which is justified 

 by the present memoir. A correct law of heredity would also be of 

 service in discussing actuarial problems relating to hereditary long- 

 evity and disease, and it might throw light on many questions con- 

 nected with the theory of evolution. 



