LITERATURE CITED * 
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——, 1954. Argentine popcorn as a modern relic of prehistoric corn. 
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Mangelsdorf, P. C., 1948. The role of pod corn in the origin and 
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——., 1953. Tests for weak alleles at the Tu-tu locus. Maize Gen. 
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* Additional literature which has a bearing on this problem, but 
which has not been directly referred to in this paper, is cited in the 
earlier paper by Galinat et al, 1956. 
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