bination they are by no means unique. In this connec- 
tion the following observations made largely on varieties 
of maize in the collections of the senior author are per- 
tinent. 
1. Uniform greenness resulting from a complete lack 
of anthocyanin coloration is indeed almost unknown, at 
least in pure form, in the indigenous maize varieties of 
Latin America. Virtually all maize, however, has at least 
a trace of anthocyanin color in the seedlings where it 
occurs in the coleoptile or leaf sheath, in the tip of the 
leaf blade, or along the leaf margins. Consequently, if 
the Assamese varieties are actually completely lacking 
in anthocyanin pigmentation, they are indeed almost 
unique. Unfortunately, the authors do not report speci- 
fically on anthocyanin color in the seedlings, stating only 
that: ‘‘The group as a whole had a strong tendency to 
green silks, green anthers, green leaves, and green culms. ”’ 
Plants of this general description are the product of two 
recessive alleles at the B and P/ loci on chromosomes 2 
and 6 respectively and of one of the lower alleles at the 
R locus on chromosome 10. Such plants are not common, 
but occur regularly throughout Latin America. In 1950, 
we grew 513 collections of corn from sixteen Latin- 
American countries. Among these were 27 varieties 
which contained plants lacking in anthocyanin color in 
the leaves, culms, silks and anthers. These occurred in 
collections from Mexico, Guatemala, Honduras, Nica- 
ragua, Colombia, Ecuador, Peru, Venezuela, Brazil, 
Uruguay and Paraguay. They had their highest fre- 
quency in the varieties of eastern South America. Of 40 
varieties from Venezuela, Brazil, Paraguay and Uruguay 
which were studied in 1950, eight, or one variety in five, 
contained some uniformly green plants compared to one 
variety in 19 for the group as a whole. So far as antho- 
eyanin coloration alone is concerned, the Assamese vari- 
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