Dichromatism in Ltfja Lappontca. 



125 



by e and /, the proportion of the pure to the mixed broods, stands 

 as 38 pure to 36 mixed in the aggregate, or, 51 +per cent : 49 — per 

 cent, a relation not materially differing from that obtained in 

 Table I from random matings within the color type S. In the 

 mixed broods the aggregate proportion of S : B is 102 1 : 345, or 

 2.98 S : I B. Table I shows the relation of S : B resulting from 

 random S X S crossings to be 3.2 S : i B. 



Table IV— Bx.B. 



From a comparison of Tables II and III it follows, therefore, 

 that here the differentiating color characters S and B follow 

 different lines of behavior in heredity, B breeding pure in second 

 generation from random parentage, and S continuing to breed 

 some pure and some mixed broods in the second generation, fol- 

 lowing Mendelian expectations for recessives and dominants. 



Experiment J. In order to determine how the color types were 

 inherited in the third generation (first generation bred from 



