Manchester Memoirs, Vol. I. (1906), No. 1|. 37 



measuring the "intensity of heredity" in a non-predicable case, 

 but it seems to me that to extend the appHcation of these means 

 to predicabJe cases is fallacious. If the true function of the 

 biometrician is to give us statistics of average conduct where we 

 cannot predict individual conduct it seems to me that to deal by 

 the biometric method with cases where we can is not only un- 

 profitable, but likely to lead men to think that where there are 

 two methods dealing with the same material of which the one 

 can predict while the other cannot, the latter is fallacious. 

 Whereas if the biometrician confined himself to the non- 

 predicable and the Mendelian to the predicable, the general 

 conclusion would be that each had his proper sphere— which 

 indeed, in my belief, he has. I do not set forth these views in 

 any spirit of dogmatic certainty ; and nothing could please me 

 less than that they should go unchallenged by anyone who 

 believes me to be mistaken. 



LITERATURE REFERRED TO IN THE TEXT. 



'08. Davy, Humphry. " On some new Phenomena of chemical 

 Changes produced by Electricity, particularly the De- 

 composition of the fixed Alkalies, and the Exhibition 

 of the new substances which constitute their bases ; and 

 on the general Nature of alkaline Bodies." Phil. Trans., 

 vol. 98, p. I. 



'89. Galton, Francis. "Natural Inheritance," Macmillan& Co. 



'95. CouTAGNE, G. "Recherches sur le Polymorphisme des 

 MoUusques de France." Lyon. 



'97. Galton, Francis. "The average Contribution of each 

 several Ancestor to the total Heritage of the Offspring." 

 Proc. Roy. Soc, vol. 61, pp. 401-413. 



'98. GuAiTA, G. VON. " Versuche mit Kreuzungen von verschie- 

 denen Rassen der Hausmaus." Ber. d. naturf. Gesell. Frei- 

 burg, vol. 10, p. 317. 



:00. . 2** Mittheilung, etc., ibid. vol. 11, p. 131. 



