416 



BOTANICAL GAZETTE 



[may 



and that from East would prove interesting. Evidently the 

 former contains something which the latter. lacks, and this some- 

 thing brings mottling instead of solid color, provided always the 

 R factor comes in with the male parent only. Such crosses should 

 help interpret this mottling, and should also reveal whether the 

 P, R, and C factors of these two investigators are identical. Four 

 crosses between C tester and East's material will be considered, 

 with the families resulting therefrom. 



TABLE I 



I. — pprrCc (East) XPPRRcc (C tester) gave 131:0:114 with 

 all the purple grains mottled, according to expectations. Obvi- 

 ously these mottled purple grains represented a PpRrCc formula, 

 the colorless PpRrCc. The number of this ear was 315, and its 

 further behavior is recorded in table I, in which the italicized 

 parent represents the immediate progeny of 315. Where mottling 

 ratios are recorded, the solid color member always precedes (2:1 

 means 2 solid color : 1 mottled). Table I shows that predictions 

 on the color ratios are fulfilled in all cases, with the possible excep- 

 tion of ear 638; while mottling ratios are similarly according to 

 prediction with the possible (one feels like saying probable) excep- 



