regularly exsert their anthers and shed pollen abundantly. 
There is no basis whatever for the suggestion (31) that 
we have, through selection, imparted fertility to a type 
of maize which never before possessed it. What we have 
done is merely to reduce the monstrosity of pod corn by 
combining the 7% gene with modifying and inhibiting 
genes, so that the glumes of the staminate spikelets no 
longer interfere with the development or release of the 
pollen. There is no type of pod corn so monstrous or so 
sterile that it cannot be changed in a few generations to 
a normal, fertile type by introducing modifying and in- 
hibiting genes from varieties of popcorn. 
(C). The comparison of pod corn to other single-gene 
anomalies in maize, especially teopod and corn grass, 1s 
not as significant as it might at first glance appear. It is 
true that both of these types exhibit certain characteris- 
tics which might be regarded as primitive (28, 24): for 
example,a freely-branching growth habit and seeds partly 
or completely enclosed by floral structures. And pod corn 
does indeed resemble teopod and corn grass in being often 
monstrous. But pod corn, however equivocal and how- 
ever monstrous, consistently and invariably has one im- 
portant characteristic which the majority of cereals have 
and which wild maize is generally assumed to have had: 
glumes enclosing the caryopses. Both teopod and corn 
grass occasionally have long glumes; more frequently, 
perhaps, they bear long spathes (9, 28). Neither of them 
consistently has the essential wild characteristic of glume- 
enclosed seeds as does pod corn. 
In an earlier publication (18), it was emphasized that 
a mutation to pod corn has never been observed in pedi- 
greed cultures, which, in the production of hybrid seed 
corn, involve large numbers of artificially pollinated 
plants. Weatherwax has contended that the failure to 
find mutations to pod corn in pedigreed stock ‘“‘need not 
[ 837 ] 
