been in the homozygous condition when removed from 
its relatives and now would give little indication of be- 
ing a fasciation. Besides this, the fasciation, if it acted 
like the one described in Trichachne, would hasten the 
divergence from its parent forms. Within the ear the 
anthers might become non-functional, although the seeds 
would continue to be produced. Tassel glumes, lemmas 
and paleas are loosely wrapped about large seeds so, if the 
size of seeds were increased, birds and insects would soon 
eliminate those plants which bore large seeds exposed on 
the tassel. 
"THE GENERAL CHARACTERISTICS 
oF SourH AMERICAN MAIZE 
The Plant 
Ordinarily the length of time to maturity is correlated 
with the number of leaves and the height of the plant, 
but when maize is grown under conditions differing from 
those of its natural habitat, this relationship is less exact. 
Maize from low altitudes requires more time to mature 
in high latitudes, while maize of temperate zones is pre- 
cocious and dwarfed in the tropics. Plant height is di- 
rectly related to length of season if allowance is made for 
the tillers. The races of maize described below vary in 
the length of time to maturity. Altiplano maize requires 
about 44 days from seed to first silk; Uchukilla, 56; 
Valle, 55 to 180; Guarani, 55 to 100 or more; Cuzco, 
90 to 140. Coroico maize grown in Cochabamba was the 
latest and most tillered of all the races. While many of 
the plants had silks after 90 days, some required 140 
before the main ear silked, and ears on the tillers were 
still far from this stage. 
Tillers range from small basal shoots which never tas- 
sel or bear ears to stalks indistinguishable from the pri- 
mary axis. Tillers are common in lowland maize. One 
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