24 BOTANICAL GAZETTE [JANUARY 
monosporangiate flowers, why are the present Monochlamydeae 
not to be regarded as the most primitive living members? This 
is because various features of the Monochlamydeae indicate 
reduction and not primitiveness. If, for example, the entire 
group as constituted by WETTSTEIN (31) be considered, it is found 
to be prevailingly syncarpous. This surely is not a primitive 
feature. Again, in various families there are closely related genera, 
even species, some of which possess a perianth, while in others it 
is rudimentary or entirely absent. It is difficult, in such cases 
at least, to conceive of the latter condition as primitive. Besides, 
the stamens and carpels may vary in number even in closely 
related genera and species. That the smaller numbers in such 
cases are derived seems to be a reasonable conclusion. Moreover, 
the inflorescences among the Amentiferae, for example, are com- 
pound structures exhibiting considerable complexity. This too 
can be more readily interpreted as derived and not primitive. 
Amphisporangiate flowers also occur in certain members of at 
least 7 families included by WETTSTEIN among the Monochlamy- 
deae. Such cases add much weight to the view that the mono- 
sporangiate condition throughout the group is secondary and not 
primitive. 
We may conclude then that considering existing angiosperms, 
the evidence at present available is in the main opposed to the 
view that they have been derived from forms at all closely related 
to the Bennettitales. The one striking similarity between modern 
angiosperms and the Bennettitales may well be a result of homop- 
lasy. Among existing angiosperms, assuming that they are 
monophyletic, the derivation of forms having monosporangiate, 
naked flowers from those possessing amphisporangiate flowers, 
bearing an undifferentiated perianth, seems far simpler than the 
reverse. So, while agreeing with ARBER and PaRKIN, HALLIER, 
and SENN in general with reference to those features which they 
believe are primitive among existing angiosperms, there seem to 
be no very adequate grounds for concluding that primitive angio- 
sperms were provided with entomophilous, amphisporangiate 
flowers bearing a perianth. The opposite seems much more 
probable. If the latter is true, scarcely a suggestion of relation- 
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