494 WEATHERWAX: SPIKELETS OF ZEA Mays 
temporarily in strains that have for a long time been monoecious 
in character, and that these reversions are, in a measure, capable 
of experimental control, offers a good field for the physiologist. 
Some of the work-of Blaringhen (1) evidently has such facts as 
Ar) 
: 
oe aes » 
oN 
ey soe OE 
ee 
Se 
ee, 
ey, 
s 
‘ee 
~~) 
[1 
~ 
Ts 
=r 
2 ep Wa 
Te 
iH 
Ls 
[) 
S, 
“<e 
A 
es 
‘oo 
Oe 
8, 
6: 
on 
Ts 
~~] 
ae 
an 
LT) 
Ne 
4 
At 
rat 
RS 
ER 
erty 
w, 
tts 
D 
Sass. 
c 
a) 
A 
ee 
Fic. 32. Lower flower of the female spikelet beginning to be disorganized, 
200. Fic. 33. Aborted flower of the female spikelet at the time of anthesis, 
X 200. S, stamen; P, pistil; L, lemma; P, palea. 
these as its basis. It is a noteworthy fact that the organs that 
are to be suppressed develop normally up to the point where 
rapid growth and sexual development begin, and then rapidly 
decline, and this suggests a lack of adequate nutrition. But, 
before proceeding far on this supposition, we must consider two 
significant facts: In either the ear or the tassel, there is a strict 
regularity in the selection of the sex to be suppressed; and it is by 
starving the whole plant, as when it is grown in a pot in the green- 
house in the winter, that perfect flowers in the tassel are likely 
to be produced. : 
SUMMARY : 
The spikelets of all varieties of maize begin to form two perfect 
flowers, and monoecism is caused by thé suppression of some part 
or parts of all the flowers. The entire lower flower of the ear 
spikelet is suppressed, except in a few varieties, and ordinarily 
only one fruit develops. 
In any single flower the development of the stamens is more 
