52 PISTILS AND STAMENS 
velopment of these kernels, the sperm portion of the endo- 
sperm nucleus dominated, and thus the endosperm is like the 
endosperm of the pollen parent. The sperm may even deter- 
mine the color and fat content of the endosperm. On the other 
hand, if Field Corn is pollinated with pollen from Sweet Corn, 
then usually the primary endosperm nucleus dominates and one 
sees no effect of the sperm. Thus it is seen that the character 
of the endosperm of a seed may be determined by either of the 
members which fused in forming the endosperm nucleus. 
The kernels in Figure 57 which have the endosperm features 
of Field Corn also have embryos with opposing tendencies. 
Fic. 58. — Pears showing a difference between the results of self- and cross- 
pollination. a, fruit resulting from self-pollination; 0, fruit resulting from 
cross-pollination. After Waite. 
These embryos received from the egg tendencies to develop into 
plants having all of the features of Sweet Corn. They also re- 
ceived from the sperm tendencies to develop plants having all 
of the features of Field Corn. In the hybrid offspring it is likely 
that some of the characters of both parents will be present. 
The Kind of Pollination Giving the Best Results. — Plants in 
general seem to favor cross-pollination and often have their 
flowers so constructed as to prevent self-pollination. In some 
plants, however, as in the small grains, Beans, Peas, and some 
other plants, self-pollination is the usual method and gives good 
results. Red clover, many fruit trees, and many other plants 
require cross-pollination and will develop very little seed or fruit 
