The Endosperm in Inheritance 153 



and each divides separately, when their progeny nuclei 

 move out to the periphery of the sac the nuclei of male 

 and female origin doubtless become more or less inter- 

 spersed. In their further division there would be groups 

 of cells of male origin interspersed among groups of 

 female origin. The result would be red and white areas 

 on the mature grain, intermingled as irregular blotches. 



Later, EAST (i) met the same phenomenon in his 

 experiments. He found, however, that sometimes 

 half the grain was red and half white, with a definite 

 boundary line between the two areas. Such a situa- 

 tion evidently did not agree altogether with WEBBER'S 

 conception of the mechanism; in fact, WEBBER himself 

 found similar cases and explains them as follows. When 

 the migration of the nuclei from the center of the embryo 

 sac to the periphery occurs, if the nuclei from the male 

 gamete have remained grouped together, as might well 

 occur, and the nuclei from the fusion nucleus have 

 remained grouped, it is probable that in their migra- 

 tion to the periphery those of one group would come 

 to occupy one portion of the periphery and those of the 

 other group the other portion. In other words, the 

 two groups would migrate en bloc to different regions of 

 the sac wall. This would lead to the production of 

 grains in which approximately half the endosperm would 

 resemble one parent and the other half the other parent. 



We have called these cases abnormal xenia. The 

 explanation is ingenious, based upon facts known to be 

 true in other seed plants. Whether these phenomena 

 occur in corn or not remains to be proved, but the 

 angiosperm embryo sac program is so uniform that 

 we can hardly doubt it. Inasmuch as corn is probably 



