252 



RAYMOND PEARL 



TABLE 3 

 Breeding index for treated matings in 1915 



as given in table 6 of X, is plotted as a solid line starting with 

 its lowest point at the left hand side of the diagram and ascend- 

 ing continuously, but at changing rates. The breeding indices 

 for the same matings, as given in table 3, are plotted as a dash 

 line. Now if it were a fact that the total reproductive capacity 

 (as here defined) of the bird in these matings diminished with 

 increasing total dosage of the gametes with alcohol or ether, 

 it clearly would be the case that the dash line would tend to 

 have its highest points at the left hand end of the diagram 

 and its lowest points at the right hand end. Or, in other words, 

 as the germ dosage line went up the reproductive capacity index 

 line would tend to go down. As a matter of fact it is obvious 

 that nothing of the sort happens. The breeding index line is 

 essentially horizontal, neither going up nor down as the value 

 of the total germ dosage index rises. 



