S. C. Harland 195 



when crossed with red, blacks, browns, maroons, and reds, appeared 

 in F^. 



(a) The cross Red by White. 



The red type used in the foregoing experiments was crossed with the 

 white (cream) seeded variety Para. The following were the results : 



The F^. The colour of the seeds of the Fi plants was exactly the 

 same as the buff type bNm, alluded to above. 



The F2. Segregation occurred into buff, red, and white. Unfor- 

 tunately only 18 plants produced seeds, but it will be seen that the 

 ratio of the three colours was close to 9:3:4. 



Plants Buff Red White 



18 11 3 4 



Expected... 10 3 5 



The F3. Sixteen families were grown in F3. Five of the buflfs 

 segregated into buff, red and white in the 9:3:4 ratio : 



Plants Buff Red White 



97 49 21 27 



Expected ... 55 18 24 



Four of the buffs threw buff and red approximately in the 3 : 1 ratio : 



Plants Buff Red 



80 62 18 



Expected ... 60 20 



Two of the buffs threw buff and white in approximately the 3 : 1 

 ratio : 



Plants Buff White 



112 78 25 



Expected ... 84 28 



Of the two reds grown in F^, one segregated into 9 red and 3 white. 

 The other gave a ratio of 15 buff, 13 red, and 12 white. Natural 

 crossing probably caused this anomalous result. 



Three whites threw whites only in F3, the number of plants in the 

 three families being respectively 96, 16, and 20. 



Interpretation of the cross Red by White. 



The results of this cross may be explained by assuming that two 

 factors are concerned : 



R the factor for a red colour of the seed coat pattern. 



N the factor for buff. This factor is without visible effect in the 

 absence of R. 



Journ. of Gen. x 14 



