PLANT Coors IN MAIzE 35 
Behavior of F, color types in later generations 
From all the foregoing it appears that the results obtained are in close 
accord with the proposed three-factor hypothesis in the case of both 
the cross purple x green and the cross dilute sun red x brown, and not 
alone for the F; and F.2 generations but also for backcrosses with green 
and with dilute sun red. It is now in order to inquire into the behavior 
of these crosses in F3 and later generations. In the presentation of the 
additional data, the two crosses purple x green and dilute sun red x brown 
will be considered together. 
Later behavior of F2 purple Ia— Purple plants of the F2 generation of 
the crosses under consideration are expected to be of eight genotypes. 
The expected F2 genetic formulae and the F; color classes, together with 
the relative numbers of each, are as follows: 
F; color types 
F; genotypes Dilute | Dilute 
Purple Sun red purple | sun red Brown Green 
Ta Ila Illa IVa VI 
i == AWA BI JIE  r 1 iad PO otetare DST al Fee h o 1 aN | De ee a (EES 
2—AABB Pipl 3 LEN ener evel Der esitpre ec ee [poeta eee 
PEP ACAG DOP UBlel eh. feesn 2 Soles Sane ALFA np oay corned Mente moe > |ncep eee: 
2—AaBB PI Pl B= | Sea S ces | eas crore 2 heer leet cee 
4 = Al ALE) JEM iene arenes 9 3 3 Loy | tees teen seat ec eee 
Me SAN B oD RL DU. ee . << sais oe 9 eal liperceceatea| leseeres ot - 3 1 
Aa= AV Gd} ILI ELS See ee eae OS Seer, Siler cars 3 1 
SAL WBN THD Fay het eine taal 27 9 9 3 9 a 
If, instead of being selfed, the F. purple plants are backcrossed to 
green of type VIc, the same F; color classes are expected but the several 
classes should, of course, be equally frequent except in case of the F» 
triple heterozygotes, which should throw three times as many greens as 
of each of the other five types. 
The F; data from thirty-five F, plants are recorded in table 8 (page 125). 
In group | of the table are listed the progenies of eight selfed and one 
backerossed F, plants. From the backcross six color types appeared 
in frequencies of 4:4:11:4:4:18. The theoretical number for the first 
