PONTEDERIA [SP.?] (PONTEDERIACEAE).
Fritz Muller found this aquatic plant, which is allied to the Liliaceae, growing
in the greatest profusion on the banks of a river in Southern Brazil. (4/15.
"Ueber den Trimorphismus der Pontederien" 'Jenaische Zeitschrift' etc. Band 6
1871 page 74.) But only two forms were found, the flowers of which include three
long and three short stamens. The pistil of the long-styled form, in two dried
flowers which were sent me, was in length as 100 to 32, and its stigma as 100 to
80, compared with the same organs in the short-styled form. The long-styled
stigma projects considerably above the upper anthers of the same flower, and
stands on a level with the upper ones of the short-styled form. In the latter
the stigma is seated beneath both its own sets of anthers, and is on a level
with the anthers of the shorter stamens in the long-styled form. The anthers of
the longer stamens of the short-styled form are to those of the shorter stamens
of the long-styled form as 100 to 88 in length. The pollen-grains distended with
water from the longer stamens of the short-styled form are to those from the
shorter stamens of the same form as 100 to 87 in diameter, as deduced from ten
measurements of each kind. We thus see that the organs in these two forms differ
from one another and are arranged in an analogous manner, as in the long and
short-styled forms of the trimorphic species of Lythrum and Oxalis.
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