A CHRONICLE OF THE TRIBE OF CORN 



233 



where on the continent before the arrival of Europeans. They are con- 

 sidered by botanists as one species. The wild relative teosinte has been 

 thought to be not only a distinct species but a member of a different 

 genus. There is good evidence, however, that there is not a much 

 greater difference between teosinte and the maize nearest like it than 

 there is between a number of the most distinct maize varieties. These 

 facts make it reasonable to suppose that both types arose from a com- 

 mon ancestor slightly different from each. 



Teosinte and maize belong to the tribe Maydese, a division of the 

 Gramineas or true grasses. Our final problem is to connect the steps in 

 the evolution of maize that distinguish it from the more typical grasses 

 and if possible to picture the restored original form. The data from 

 which one can do this come from observations of thousands of crosses 

 between the different maize varieties. 



Fig. 10. A Rare Reversion to Perfect Flowers. 

 Note the stamens around the seeds. 



Sweet corn is probably the most recent type. Sweet corns are simply 

 dent, flint, pop and floury types that have lost the ability to mature 

 starch grains. This is proved by crossing it with starchy kinds. For 

 example, dent corns crossed with certain sweet corns produce flint types 

 in the second hybrid generation. Starchiness is put into the hybrid by 

 the dent variety and the latent flintiness of the sweet variety appears. 



In the same way crossing indicates that as the pop or poplike va- 

 rieties increased in size by numerous slight variations, the flint, the 

 dent, and the floury kinds were produced through the correlation be- 

 tween the structure of the seeds and their size. This brings us back to 

 a many-branched pop-like variety, examples of which are common 

 enough to-day. 



Most maize varieties have naked seeds, a feature unlike other 

 grasses including teosinte. The remaining members of the familv have 



