WEATHERWAX: THE EVOLUTION OF MAIZE 
The aerial part of the 
typical maize plant (Fic. 1) 
consists of a tall, jointed stem, 
provided with  distichous 
leaves, and bearing in the 
axil of each leaf, except pos- 
sibly some of the upper ones, 
a potential branch. Some of 
these branches do not nor- 
mally develop, and microtome 
sections are sometimes neces- 
sary to disclose their rudi- 
ments. One or more near 
the middle of the stem develop 
into ear-bearing shoots. The 
lowest branches, arising at or 
below the surface of the 
Fic, 2. A typical male inflorescence of corn. 
’ 
The main stem terminates in a 
Male «nflorescence.—The 
terminal panicle of spikelets 
(FIG. 2) is made up of a num- 
ber of simple or branched 
lateral organs attached to a 
central axis which terminates 
in a spike. The spikelets are 
borne in pairs, one pedicelled 
and the other sessile (Fics. 3, 
5). Occasionally in all, and 
very regularly in a few varie- 
ties, groups of three or more 
are found (Fic. 4), instead of 
pairs of spikelets, and in such 
Fic. 3. Portion of .the central spike 
of a corn tassel. Fic. 4. A group of 
spikelets, such as often occurs itistead of 
a pair. Fic. 5. Spikelets on the lateral 
rachis of a corn tassel. 
a group one is usually pedi- 
celled. Both of a pair or all 
of a larger group are occasion- 
ally sessile. In’ the typical 
