of ear, is strikingly revealed by ears from a cross of pod 
corn (tunicate maize) with a variety of maize obtained 
from the Guarany Indians of Paraguay. The Guarany 
maize has many peculiar and interesting characteristics. 
It is one of the few varieties from the lowlands of South 
America whose chromosomes are knobless or almost so. 
It exhibits almost all of the dominant genes known in 
maize, a condition to be expected in a primitive variety. 
It has the most slender and most flexible rachis ever en- 
countered in a cultivated variety of maize. Finally, it 
has the peculiar characteristic, under some conditions, of 
exhibiting in the ear an indeterminate habit of growth. 
When this happens the ear protrudes far beyond the 
husks and the exposed region of the ear becomes greatly 
elongated to produce a lax and flexible spike. This con- 
dition was first encountered in 1941. An attempt made 
in 1942 to induce it through treatment did not succeed. 
In 1944 the condition again occurred spontaneously. 
What the factors are which are involved inits occurrence 
isnot known. Bonnett (8) states that both staminate and 
pistillate inflorescences in maize are potentially indeter- 
minate. Apparently the potentiality persists for a longer 
period in the Guarany maize than in ordinary maize and 
an opportunity is afforded for environment to play a part. 
It is of some interest in this connection to note that the 
indeterminate nature of the ears was much more pro- 
nounced in a late-planted row which flowered during a 
period of very favorable weather, than it was in earlier 
planted rows which came into bloom during a hot dry 
period. 
The stock in which the indeterminate ears occurred in 
1944 was one which had been derived from a hybrid of 
Guarany maize and pod corn which had been twice back- 
crossed to Guarany and was therefore seven-eighths Gua- 
rany in its germplasm. ‘Tunicate and non-tunicate ears 
[ 50 | 
