STUDIES IN THE DEVELOPMENT OF THE PIPERACEAE 735 
or less inhibited in certain flowers from expressing itself as a con- 
trolling factor in the development of tissues in the flower rudi- 
ment. That is femaleness is unusually more or less dominant 
over the male tendency. (Shull, '10, p. 119.) Or, we must 
assume that an absolute segregation of the sex-determin- 
ing substances may occur at very different times in different 
spikes, in different flowers of the same spike, or even in different 
stamens of the same flower. Of these two views the former seems 
much more probable from the facts above given. It also agrees 
with the results, previously referred to, of the work of Correns 
('08) and Strasburger ('09) on gynomonoecious angiosperms. 
The same condition is clearly indicated also by the work of the 
Marchals ('07) on those diploid gametphores of the mosses, in 
which, while some individuals bore both antheridia and arche- 
gonia, i.e., the flowers were hermaphrodite, other individual gam- 
etophores, as long as kept, bore only one kind of sexual organ each. 
From all the evidence now available we are warranted in assum- 
ing the possibility of the presence of the second sex in many of 
those angiospermous sporophytes where only one sex has thus 
far been detected. The best evidence for this assumption being 
found in the fact that in certain known cases the application of 
the proper stimulus may cause this second sex to become evident, 
by the development of its proper reproductive organs. (Morgan, 
'09, p. 337, 346.) 
If then the flower of Piper betel is potentially hermaphrodite, 
what is the cause of the suppression, partially or wholly, of the 
sporogenous tissue or even of the sporophyll itself, now of the 
stamens, now of the carpels or now of both? What, in certain 
stamens, is the cause of the extension of the sporogenous tissue 
across the whole width of the anther? That space relations, or 
the crowding of the parts of the flower in the bud, do not consti- 
tute the determining factor seems evident from the fact that the 
sporogenous tissue of the microsporangium, e.g., may be sup- 
pressed or extended now in the upper, now in the lower theca 
of the stamen, while, less frequently, it may occur in both, or 
extend across from one theca into the other (figs. 9, 24-31). There 
is likewise no indication of the localization of these abnormal 
