MARSH ST.JOHN'SWORT

(Triadenum Virginicum; Elodea Virginica of Gray) St.-John's-wort family 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 capsule. 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 of Ophelia, "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 a mistake.

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