May, 1920.] 



YASTJI:— GENETIC Al STUDIES. 



57 



may expect that they will be found later to belong to some flavone 

 derivations. 



4. The cell-sap of white flowers does not react to ammonia 

 vapour ; and neither aqueous nor alcoholic extract produces red 

 cdlour, by usual reducing method for flavone derivations, so that we 

 may conclude that the white colour of the petal is due to the 

 absence of the chromogen. There is one thing to be considered, 

 however, that is, the presence or absence of the reducing factor which 

 I will describe afterwards in this paper. 



BREEDING EXPERIMENT 

 A. Doubleness and Singleness of the Flower 



Experiment 1. A scarlet single individual (Fig. I. 1) mated with 

 a white double individual (Fig. I. 2) gave a magenta double Fi plant 

 (Fig. I. 3). The result of mating the pure white single with the pollen 

 of the just mentioned magenta double is given in the table 1. 



Fi-. I. 





1. A Single (P 4-) 



2. A Double (P <?) 



3. One of F t plants. 



