No. 566] INHERITANCE IN EARS OF MAIZE 109 



stance that Mirabilis has perfect flowers while Zea is 

 monecious. In Mirabilis both male and female gametes 

 of a green branch arise from somatic cells in which the V 

 factor has changed to a G factor. If a change in only one 

 V factor is responsible for the production of the green 

 branch, the somatic cells of such a branch must all be VG 

 and the results reported by Correns are the only ones to 

 be expected. With Zea mays, however, all the grains of 

 one ear of a variegated-eared plant might arise from cells 

 having VS, so that half of the female gametes would carry 

 S, while little or no corresponding change might take 

 place in the staminate inflorescence and therefore no (or 

 very few) male gametes would carry S. From such an 

 ear of maize only about one half, instead of three fourths, 

 of the F 1 plants should have red ears and none (or very 

 few), instead of one third, of the F t plants should breed 

 true. 



The occasional green plants ("a" per cent.) arising 

 from variegated branches in Correns 's experiments with 

 Mirabilis are more nearly comparable to Fj red-eared 

 maize plants than are the green plants arising from green 

 branches. It is quite conceivable that on a variegated 

 branch the male gametes might arise from cells that are 

 VG, while the female gametes arise from cells that are 

 VV, or the reverse, though this difference between male 

 and female gametes would hardly be so common an occur- 

 rence as with maize where the staminate and pistillate in- 

 florescences are situated so far apart. It is worthy of 

 note in this connection that of the occasional green plants 

 produced by selfed seed of variegated plants in Correns 's 

 experiments with Mirabilis (see diagram, Fig. 2), less 

 than one third bred true and more than two thirds segre- 

 gated into green and variegated. (Correns indicates this 

 merely by the signs < and > in connection with 33 per 

 cent, and 66 per cent, respectively, in his diagram, and 

 gives no indication of how much less than 33 per cent, 

 bred true or how much more than 66 per cent, segregated.) 



De Vries's results with Antirrhinum yield readily to 



