This species opens its petals only by night. The calyx is somewhat swollen, 1 inch long. Leaves, long, narrow, tapering to a point.
The pretty, fragrant flowers invite the night-moths by throwing open their petal doors by night. in the daytime they are only wilted, uninteresting flowers.
Mr. W. H. Gibson says: " ' Is not the midnight like Central Africa to most of us?' asks Thoreau; and not without reason. for even the best-informed student of daylight natural history may visit his accustomed haunts in the darkness as a pilgrim in a strange land. At least once in the summer to light our lantern and walk among the flowers would well repay us, for the flowers and leaves asleep are a strange, unwonted sight. And occasionally the rule is reversed, as in the case of the night-flowering catchfly, and the flower, like some belle of the ball dressed in white, is awake, entertaining insect guests, to whom her portals are closed by day."