234 Harshbcrger — A Study of the Fertile Hybrids 



the kernels are larger, more rounded and more floury, 

 while the corneous cucullate depression of the rhachis has 

 become smaller and more saucer-like (Fig. 3). The kernels 

 of this generation are usually arranged in a distichous manner. 

 The third year, pollen of Indian corn is again used, and the 

 resulting ears are found to differ by the increase of the num- 

 ber of rows of grains, four or more being found ; the pithy 

 axis (cob) now becomes demarcated, and is seen when the ear 

 is broken across (Figs. 4 and 5). The plants of this genera- 

 tion and the fourth (Figs. 6, 7 and 8) are identical with those 

 described by Professor Watson and myself^ 



The cross thus established between teosinte and maize may 

 be represented as follows : 



EiichlcBua mexicana Schrad. 9 X Zea mays L. J^ = Zea can- 

 ina Watson, the " maiz de coyote," or " maiz de los gentiles " 

 of the Mexicans, 



Before closing, it is important to refer to two interesting 

 facts. The hybrids described above are known widely through- 

 out Mexico. Dr. Carl Lumholz found ears identical with 

 those of the hybrids among the timid Tarahumara Indians of 

 northern central Mexico, who, in their mountain fastnesses, 

 come little in contact with white men. Dr. Nicolas Leon also 

 informs me that the hybrids are grown by the Mixes and 

 Zapotecs inhabiting the State of Oaxaca, and that there the 

 plant is quite common. 



Corn smut {Ustilago zece) also occurs on the hybrids 

 especially those of the fourth generation, as so clearly shown, 

 in the photograph (Fig. 9). 



Conclusions, 



With these interesting hybrids before him, one is tempted to 

 theorize. Is Zea mays a true species, or is it a cultivated race 



^ A very fair but reduced illustration of the ears of the fourth hybrid generation 

 is to be found in my monograph. — Bot. Contrib., Univ. Penn., I, plate xv, fig. 9. 



