82 
IOWA ACADEMY OF SCIENCE 
In brief, this form displays a type of flower and a inode of pollination 
apparently not hinted at in previously described species and offers the 
sharpest contrast to the habit of releasing the pollen bearing flowers with- 
out elongation. Biologically this trait is of interest as suggesting two 
unlike and probably independent types of evolution in this genus in the 
efforts of this plant to meet the difficulties of pollination in its habitat. 
The first and simpler, and doubtless the more primitive, is seen in the 
short-stalked flowers that come to nothing unless detached. The second 
and probably derived condition is seen in the attempt, often successful, 
to reach the surface by elongation of the axis, the plan regularly em- 
ployed by the pistillate flower. The subsequent detachment of the stami- 
nate flowers may be due to the breaking down of tissues in the now 
useless structure. 
The pistillate flower and the vegetative body conform more nearly to 
the described species, but in both departures were noted from the com- 
mon type. In the opinion of the writer this form may deserve specific 
rank, and the name Elodea loivensis {Philotria loivensis) is proposed 
should it prove to be a new species. Further observations wflll be car- 
ried on this coming summer, and a more detailed description prepared 
in due time. 
