THE DETERMINATION OF DOMINANCE. 



Z^^J 



In as much as this experiment was conducted in a large cage 

 and not in the open, it was manifestly impossible to utilize all 

 the individuals which emerged, so a reduction was made for the 

 matings for Fg, excepting that any extreme or rare types were 

 given every advantage over the more common types. The fol- 

 lowing materials were selected at random from the different 

 groups as parents of the second generation: 



These inbred rapidly during July and at the end of August gave 

 a second generation which was uniformly an intermediate be- 

 tween L. decemlineata and L. oblongata. 



This was especially true of the adult characters. The larval 

 characters, however, were also variable and appeared to be less 

 blended into a homogeneous group. 



The culture hibernated from early September, 1906, to June, 

 1907. During this period a very great mortality occurred, which 

 was due very largely, I think, to the fact that the culture would 

 probably have reproduced a third time in 1906 if it had been 

 supplied with food and proper conditions. 



These individuals in 1907 reproduced and gave a pretty uniform 

 progeny of the blended type between L. decemlineata and L. 

 oblongata, generation III. 



A fourth generation was obtained in late August and early Sep- 

 tember of the same year, which possessed the same attributes as 

 the third generation. In nature, this culture was not carried 

 beyond that stage, but material from the culture was brought 

 to Chicago and carried through the winters of 1907 and 1908, 



