At the right, an ear of sweet corn; at the left, ears of Teosinte; in the middle, hybrids between the two. Teosinte is believed to be the original stock from which the developed corn sprang. The ear of Teosinte, however, suggests the head of wheat rather than the seed-group of its developed descendant.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 8 Chapter 1