Corn Self-Pollenated and Crossed With Teosinte
The upper ear is an ordinary ear of corn, presenting no marked peculiarities. The lower ear was developed by pollenizing the corn with pollen from the primitive type of corn called teosinte, which is illustrated in earlier pages of the present volume. The influence of the pollen-parent is clearly shown in the modified form of the kernels. With most plants the pollen does not directly effect the fruit, but corn is an exception in this regard.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 3 Chapter 3