Sundrops.
Œnothera fruticosa. Evening Primrose Family.

This is a day-blooming species of the evening primrose, with large, pale yellow blossoms and alternate oblong or narrowly lance-shaped leaves, and of a much less rank habit. In early summer our roadsides are illuminated with these flowers.

Œnothera pumila is also a diurnal species. Its loosely spiked blossoms are much smaller than those of the sundrops.

Evening Primrose.
Œnothera biennis. Evening Primrose Family.

Stout, erect, one to five feet high. Leaves.—Alternate, lance-shaped to oblong. Flowers.—Pale yellow, in a leafy spike, opening at night. Calyx.—With a long tube, four-lobed. Corolla.—Of four somewhat heart-shaped petals. Stamens.—Eight, with long anthers. Pistil.—One, with a stigma divided into four linear lobes.

Along the roadsides in midsummer we notice a tall, rank-growing plant, which seems chiefly to bear buds and faded blossoms. And unless we are already familiar with the owl-like tendencies of the evening primrose, we are surprised, some dim twilight, to find this same plant resplendent with a mass of fragile yellow flowers, which are exhaling their faint delicious fragrance on the evening air.

One brief summer night exhausts the vitality of these delicate blossoms. The faded petals of the following day might serve as a text for a homily against all-night dissipation, did we not know that by its strange habit the evening primrose guards against the depredations of those myriad insects abroad during the day, which are unfitted to transmit its pollen to the pistil of another flower.

We are impressed by the utilitarianism in vogue in this floral world, as we note that the pale yellow of these blossoms gleams so vividly through the darkness as to advertise effectively their whereabouts, while their fragrance serves as a mute invitation to the pink night-moth, which is their visitor and benefactor. Why they change their habits in the late year and remain open during the day, I have not been able to discover.

Horse Balm. Rich-weed. Stone-root.
Collinsonia Canadensis. Mint Family (p. [16]).

One to three feet high. Leaves.—Opposite, large, ovate, toothed, pointed. Flowers.—Yellowish, lemon-scented, clustered loosely. Calyx.—Two-lipped, the upper lip three-toothed, the lower two-cleft. Corolla.—Elongated, somewhat two-lipped, the four upper lobes nearly equal, the lower large and long, toothed or fringed. Stamens.—Two (sometimes four, the upper pair shorter), protruding, diverging. Pistil.—One, with a two-lobed style.