kempton: ancestry oe maize 7 



Contrary to Weatherwax's assertion, there is in reality no 

 mathematical difficulty involved in developing ears with ten, 

 fourteen, or eighteen rows by the fasciation of 4-rowed branches. 

 Ears having rows in these numbers can be obtained by the 

 abortion of a row of paired spikelets or the abortion of the pedi- 

 celled spikelets of one of the component branches, both of which 

 phenomena are of rather frequent occurrence. Moreover, the 

 writer is inclined to believe that a statistical investigation would 

 probably show varieties with ten, fourteen, and eighteen rows 

 to be less common than those having rows that are multiples 

 of 4. The ver}^ large number of 8-rowed varieties and th- 

 complete absence of 6-rowed varieties have also to be cone 

 sidered. 



In view of the fact that maize is intermediate in a great many 

 respects between the specialized characteristics of teosinte and 

 the more primitive characteristics found in pod corn, Collins 

 conceived the idea that it probably originated as a hybrid be- 

 tween teosinte and a primitive grass having many of the char- 

 acteristics of pod corn. Weatherwax's contention that pod 

 com can not be accepted as a "primitive type" seems beside the 

 point, since no one but the very early writers has held such a 

 view. The various types of pod corn do, however, afford a 

 series of characters that may properly be called primitive, since 

 they are shared by many species of Andropogoneae. The fact 

 that these characters are not all combined in a single mutation, 

 but have occurred independently in various combinations, would 

 seem to strengthen rather than weaken this evidence that they 

 are ancestral. And since there is no genetic obstacle to uniting 

 the characters of the various types by properly selected matings, 

 there can be no objection to their theoretical combination. 

 Furthermore, since pod corn appears as mutations from highly 

 specialized commercial varieties, there surely need be no surprise 

 that the so-called earless plants have undeveloped ear buds in the 

 axils of their leaves. 



A confusion of terminology doubtless accounts for the dis- 

 agreement between Collins and Weatherwax on the presence of 

 staminate flowers in the branches of pod corn. There are, of 



