MAYDEA 161 
202. Zea L.—Indian corn, maize. This genus is 
represented only by the cultivated maize (Z. mays L.), 
and is not known in the wild state. There are several 
well-marked varieties, such as dent, pop and sweet, which 
are thought by some to be distinct species. Like the pre- 
ceding genus, the staminate inflorescence is separate from 
the pistillate. The former is a terminal panicle called the 
tassel and the latter, a thick spike surrounded by leafy 
bracts or husks, is called the ear. The staminate spikelets 
are in pairs on the rachis, 1 sessile and the other pediceled, 
each 2-flowered, the thin lemmas and paleas being shorter 
than the firm glumes. The ear consists of several close 
rows of pistillate spikelets upon a greatly thickened axis, 
the cob. The spikelet consists of 2 glumes, a sterile lemma 
with a small palea, and a fertile lemma and palea. All 
these bracts remain at the base of the mature grain as 
coriaceous chaff on the cob. The numerous single styles 
protrude from the ear and form the “‘silk.”” There is a 
potential ear in every leaf-axil but usually only one de- 
velops into a perfect ear. In one variety, called pod-corn, 
each kernel is enveloped in the elongated floral bracts. 
There has been much speculation as to the origin of corn. Some 
have thought that it has been developed from Teosinte, others that 
the original wild form has become extinct. It is more likely that it is 
a hybrid between Teosinte and an unknown or extinct species re- 
sembling pod-corn. (Collins ‘““The Origin of Maize,” Journ. Wash. 
Acad. Sci. 2:520. 1912.) 
Corn has been cultivated from prehistoric times by 
the early races of American aborigines, from Peru to 
middle North America, and is now cultivated throughout 
the world in warmer regions for food for man and do- 
mestic animals. The chief varieties are dent, the common 
commercial field variety, flint, formerly common in the 
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