Manchester Memoirs, Vel. I. (1906), No. 11. 



25 



given hybrid is from the first hybrid , the fewer 



pure recessive and dominant forms is it likely to produce 

 when mated with another hybrid of its own generation." 

 r. For the very good reason that I did not then understand 



it : as I do now. 

 If " Law of Contribution " is put in the place of the terms 

 2, 3, and 4, this passage is quite true. As it stands, 

 it is nonsense. 



Perhaps, after all, the most complete example of this 

 confusion is to be found in Castle's writings : it occurs 

 in his paper on Galton's and Mendel's Laws : he gives 

 a table * to shew the difference between the Mendelian 

 and Galtonian prediction of the number of albinos pro- 

 duced by crossing Japanese waltzing mice with albino, 

 together with the actual numbers that occurred in von 

 Guaita's well known experiment.f 



I give the top 2 lines of the table. 



Substitute Law of Contribution for Galton's Law, and 

 the idea conveyed by the Table is sensible and true. 



I will refer to one more passage in which Galton's 

 Law is used in the sense of the Law of Contribution : 

 " Nach Gallons Theorie muss jede Gamete, welche von 

 einem Individuum produziert wird, imstande sein, alle 

 Merkmale der Sippe, welcher es angehort, auf die Nach- 

 kommen zu ubertragen ; es ist unmoglich, dass gewisse 

 Gameten fUr immer von der Ubertragung gewisser 



* Castle :03, p. 231. 

 t Guaita '98 :oo. 



