(Triadenum Virginicum; Elodea Virginica of Gray)
Flowers - Pale magenta, pink, or flesh color, about 1/2 in.
across, in terminal clusters, or from leaf axils. Calyx of 5
equal sepals, persistent on fruit; 5 petals; 9 or more stamens
united in 3 sets;
pistil of 3 distinct styles. Stem: to 1 1/2 ft.
high, simple, leafy. Leaves: Opposite, pale, with black,
glandular dots, broadly oblong, entire edged, seated on stem or
clasping by heart-shaped base. Fruit: An oblong, acute, deep red
Preferred Habitat - Swamps and cranberry bogs.
Flowering Season - July-September.
Distribution - Labrador to the Gulf, and westward to Nebraska.
Late in the summer, after the rather insignificant pink flowers
have withered, this low plant, which almost never lacks some
color in its green parts, greatly increases its beauty by tinting
stems, leaves, and seed vessels with red. Like other members of
the family, the flower arranges its stamens in little bundles of
three, and when an insect comes to feast on the abundant pollen -
no nectar being secreted - he cannot avoid rubbing some off on
the stigmas that are on a level with the anthers. He may
sometimes carry pollen from blossom to blossom, it is true, but
certainly the St.-John's-wort takes no adequate precautions
against self-fertilization at any time. Toward the close of its
existence the flower draws its petals together toward the axils,
thus bringing anthers and stigmas in contact.
SPIKED WILLOW-HERB; LONG PURPLES; SPIKED or PURPLE LOOSESTRIFE
(Lythrum Salicaria) Loosestrife family
Flowers - Bright magenta (royal purple) or pinkish purple, about
1/2 in. broad, crowded in whorls around long bracted spikes.
Calyx tubular, ribbed, 5 to 7 toothed, with small projections
between. Corolla of 5 or 6 slightly wrinkled or twisted petals.
Stamens, in 2 whorls of 5 or 6 each, and 1 pistil, occurring in
three different lengths. Stem: 2 to 3 ft. high, leafy, branched.
Leaves: Opposite, or sometimes in whorls of 3; lance-shaped, with
heart-shaped base clasping stem.
Preferred Habitat - Wet meadows, watery places, ditches, and
banks of streams.
Flowering Season - June-August.
Distribution - Eastern Canada to Delaware, and westward through
Middle States; also in Europe.
Through Darwin's patient study of this trimorphic flower, it has
assumed so important a place in his theory of the origin of
species that its fertilization by insects deserves special
attention. On page 5, the method by which the pickerel weed,
another flower whose stamens and pistil occur in three different
lengths, should be read to avoid much repetition. Now the
loosestrife produces six different kinds of yellow and green
pollen on its two sets of three stamens; and when this pollen is
applied by insects to the stigmatic surface of three different
lengths of pistil, it follows that there are eighteen ways in
which it may be transferred. But Darwin proved that only pollen
brought from the shortest stamens to the shortest pistil, from
the middle-length stamens to the middle-length pistil, and from
the long stamens to the long pistil effectually fertilizes the
flower. And as all the flowers on any one plant are of the same
kind, we have here a marvelous mechanism to secure
cross-fertilization. His experiments with this loosestrife also
demonstrated that "reproductive organs, when of different length,
behave to one another like different species of the same genus in
regard both to direct productiveness and the character of the
offspring; and that consequently mutual barrenness, which was
once thought conclusive proof of difference of species, is
worthless as such, and the last barrier that was raised between
species and varieties is broken down." (Muller.)
Naturally the bright-hued, hospitable flower, which secretes
abundant nectar at the base of its tube, attracts many insects,
among others, bees of larger and middle size, and the butterflies
for which it is especially adapted. They alight on the stamens
and pistil on the upper side of the flower. Those with the
longest tongues stand on one blossom to sip from the next one:
this is the butterfly's customary attitude. But nearly every
visitor comes in contact with at least one set of organs. When
Darwin first interpreted the trimorphism of the loosestrife, we
can realize something of the enthusiasm such a man must have felt
in writing to Gray: "I am almost stark, staring mad over
lythrum.... For the love of Heaven have a look at some of your
species, and if you can get me some seed, do!"
Long ago this beautiful plant reached our shores from Europe, and
year by year is extending its triumphal march westward,
brightening its course of empire through low meadows and marshes
with torches that lengthen even as they glow. It is not a spring
flower, even in England; and so when Shakespeare, whose knowledge
of floral nature was second only to that of human nature, wrote
"With fantastic garlands did she come,
Of crow-flowers, nettles, daisies, and long purples,"
is it probable he so combined flowers having different seasons of
bloom? Dr. Prior suggests that the purple orchis (0. mascula)
might have been the flower Ophelia wore; but, as long purples has
been the folk name of this loosestrife from time immemorial in
England, it seems likely that Shakespeare for once may have made
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