839 



and in such a manner that the proportional figures sliow that either 

 all three segregate independently of one another, or that two are 

 correlated and the third remains free or that all three arc correlated. 

 On Baur's hypothesis this phenomenon is easily explained. The 

 factors A, B, and C may be distributed over the three chromosomes 

 as follows: 



1. A, B, and C all in 1 chromosome, e.g. m I. 



2. A and B together in one chromosome, e.g. in I and C in 

 another, e.g, //. 



, 3. A, B, and C in three different chromosomes e.g. A in /, B in 

 //, and C in ///. 



By substitution all other possible combinations can be found, which, 

 however, give no other proportional figures than the examples given, 

 which can be represented, as on page 148 of this book Baur repre- 

 sents them, e.g. by black for the chromosomes of the "red" plants 

 and white for the "green" ones. The formulae of the reproductive 

 cells appear theji as follows : 



Proceedings Royal Acad. Amsterdam. Vol. XVI. 



54 



