BRIEFER ARTICLES. 
THE STRUCTURE OF THE FLOWERS AND THE MODE 
OF POLLINATION OF THE PRIMITIVE ANGIOSPERMS. 
Tue purpose of this paper is to show how some questions involved | 
in the phylogeny of angiosperms might be regarded from the point of 
view of the anthoecologist. The proposition to be offered is that the 
primitive angiosperms were entomophilous, and that the anemophilous 
ones are metamorphosed entomophilous flowers whose seemingly simple 
structures are degraded, not primitive. 
The characteristic anemophilous flower has a pistil with a one-celled 
ovary containing a single ovule and ripening into a one-seeded indehis- 
cent fruit. The characteristic entomophilous flower has a pistil with 
several ovules which ripens into a several-seeded dehiscent fruit. The 
explanation of the monospermy of the Anemophilae and the poly- 
‘spermy of the Entomophilae is obvious when one considers the differ- 
ence in the conditions of pollination. Even with a large plumose 
stigma the Anemophilae have enough to do to secure enough pollen 
for a single ovule. The Entomophilae with a small stigma can readily 
secure enough pollen for many ovules. The relation of many-seeded 
fruits to entomophilous pollination is emphasized in the orchids, where 
the high degree of polyspermy is correlated with the disposal of the 
pollen in masses. There are conditions under which entomophilous 
flowers become monospermous, and anemophilous flowers derived from 
them may show monospermy as an inherited character. But poly- 
spermy is an entomophilous character. 
Syncarpy involves polyspermy and is also an entomophilous charac 
ter, the union of oligospermous fruits producing polyspermy. It 18 
hard to imagine conditions under which an anemophilous plant would 
be likely to become syncarpous. Accordingly, in the absence of other 
entomophilous characters, and in spite of the presence of anemophily, 
plants may still retain the entomophilous characters of polyspermy and 
syncarpy. Syncarpy is important in diagnosing advanced stages of 
anemophilous metamorphosis because indications of syncarpy ™ay be 
the only remaining evidence of a previous polyspermous condition. I 
also regard highly specialized inflorescences as entomophilous. At any 
; 294 [APRIL 
