1922] CURRENT LITERATURE 157 
given to selfing of individual plants with some success. In order to hasten 
the work, winter seed growing in the greenhouse or out-of-doors in the southern 
states was practiced with moderate success. 
Seedsmen and growers are interested in the possibility of producing seed of 
these resistant strains in the commercial cabbage seed growing sections. The 
difficulty encountered in this procedure lies in the fact that yellows does not 
occur generally in our seed growing sections. The small percentage of sus- 
ceptible plants would thus not be eliminated, and tendency toward reversion 
would be expected. The investigators have studied this question by having 
a resistant strain grown for one generation in the Puget Sound seed growing 
section, and then testing it on diseased soil together with Wisconsin grown 
strains. Little or no reversion was noted when this was carried on for only one 
generation. The practice, therefore, is being approved for the present pro- 
vided precautions are taken to supply stock seed each year from plants selected 
on diseased soil, and to so isolate seed fields as to avoid all possibility of cross- 
pollination with other varieties.—J. C. WALKER. 
Abnormal behavior in corn endosperm.—If pollen from red grained corn 
= nga to the silks of a colorless grained variety, the resulting grains will 
his familiar phenomenon of xenia is explained by the known facts of 
double fertilization. This cross, however, may produce a very few aberrant 
Sach grains are commonly spoken of as “ mosaics,” while the terms 
“spotted,” and “variegated” usually refer to different phenom WEBBER™ 
observed this phenomenon, and suggested two possible At aeth (x) the 
second male nucleus fails to fuse with the female fusion nucleus, and these two 
elements divide independently in producing endosperm; (2) the second male 
nucleus fuses with one of the female polars, the other polar dividing independ- 
ently in the production of endosperm. 
The first explanation was disproved by East” in the following manner. 
Factors R and C must be present simultaneously for the production of red 
endosperm. A cross between the two colorless grained types, CCrr and ccRR, 
therefore, will produce a red grained ear. Even here, however, aberrant 
grains sometimes appear, part of the grain being white and the rest colorless. 
Failure of the second male nucleus to fuse with the female polar nucleus in such 
a case would result in a grain which was entirely colorless, a thing which never 
occurred. It is only by fusion of male and female nuclei that any part of the 
endosperm can be red. 
™ WEBBER, H. J., Xenia, or the ces ae of pollen in maize. U.S. Dept. 
Agric., Div. Veg. Phys. Path, Bull. 22:1-44. 
@ East, E, M., Xenia and the endosperm s angiosperms. Bort. Gaz. 56:217-224. 
1913. 
