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Variation and Varieties of Zea Mays. 



Paul Weatherwax, Indiana University. 



Indian corn is commonly known to be a very variable plant, and any 

 farmer can name off-hand from a dozen to fifty more or less definite 

 varieties. Many attempts have been made to dispose of the plant in a 

 technical vi^ay by naming, describing, and classifying these varieties, but 

 the layman, and even the botanist who has not made a special study of 

 the subject, is much in the dark as to what nomenclature is advisable 

 in speaking scientifically of corn. To point out briefly the range of vari- 

 ability of the plant and to discuss critically some of the technical names 

 that have been applied to the varieties of corn is the object of this paper. 



In all parts of the maize plant there is a striking variability of 

 size. I have grown healthy plants in a normal environment which were 

 eighteen inches tall at maturity; and plants twenty-four feet tall have 

 been reported. Some plants have stems no larger than a lead pencil, and 

 the stems of others measure six inches in circumference. The leaves and 

 other vegetative parts vary proportionately. 



Stalks of most varieties bear only one or two ears, but as many as 

 ten well-developed ears have been seen on a single stalk. An ear may 

 have from four to thirty rows of grains, and there is as great a variation 

 in the number of grains in a row. 



The fruit of the plant, being the economic part and the part best 

 known, has been made the basis of most classifications. The pericarp 

 varies from white through shades of pink, red, and yellow to a dark 

 brown, and definite color patterns in the form of stripes are common. 

 The endosperm is usually characterized by the development of a large 

 amount of starch, but in sweet corn the starch is partly replaced by an- 

 other carbohydrate. In physical character the endosperm is partly soft 

 and partly corneous, and these parts have a more or less definite ratio 

 and arrangement in each variety. The soft portion is always white; the 

 corneous part may be white or yellow. The aleurone is white, red, or 

 blue to black, and mixtures of either of these colors with white occur in 

 definite patterns in some varieties. The largest grain I have ever seen 



