The Salvia, or Scarlet Sage

Lesson CLXI

The Bachelor’s
Button

Leading thought—Each bachelor’s button is made up of many little flowers which may be studied by the outline given in Lesson CXXXV.

Teacher’s Story

The flower story of the sage is so peculiar that Darwin has used it to illustrate the mechanisms present in some flowers which the visiting insects must work in order to get the nectar. The scarlet sage, which gladdens our flower beds during the summer and autumn with its brilliance, has as interesting a story as has any of its family. Looking at it from the outside, we should say that its nectar-wells lie too deep to be reached by any insect except a moth or butterfly, or a humming bird; there is no platform for a bee to alight upon, and the tube is too long to be fathomed by a bee’s tongue; but the bees are very good business folk; they adapt themselves to flowers that are not adapted to them, and in autumn the glow of the salvia attracts the eye scarcely more than the hum of the visiting bees attracts the ear.

The calyx of the salvia is as red as the corolla, and is somewhat fuzzy while the corolla is smooth. The calyx is a three-lobed bulging tube held stiff by rather strong veins; there is one large lobe above and two small ones below the corolla. The corolla is a tube which is more than twice the length of the calyx; it is prolonged above into a projecting hood, which holds the anthers and the stigma; it has a short, cuplike lower lip and two little turned-back, earlike lobes at the side.

The special mechanism of the salvia is shown in the stamens; there are two of these lying flat along the floor of the corolla-tube and grown fast to it. Near the mouth of the tube, each of these lifts up at a broad angle to the roof, and is more or less T-shaped, at the tip of one of the arms of the T is an anther while the other arm is longer and slants down and inward to the floor of the tube, as shown at 2 in the figure.

The bee visiting the flower and entering the corolla-tube, pushes her head against the inner arms of the stamens, lifting them, and in so doing causes the anthers on the front arms of the T to lower and leave streaks of pollen along her fuzzy sides. The stigma is at first concealed in the hood; but, when ripe, it projects and hangs down in front of the opening of the corolla-tube, where it may be brushed along one side or the other by the visiting insect, which has been dusted with the pollen of some other flower. The stigma-lobes open in such a manner that they do not catch the pollen from the insect backing out of their own corolla. As the nectar is at the base of the corolla-tube, the bees, in order to get it, crawl in almost out of sight. Late in the season they seem to “go crazy” when gathering this nectar; I have often seen them searching the bases of the corolla-tubes which have fallen to the ground, in order to get what is left of the sweet treasure.

But the pollen story is not all that is of interest in the salvia. Some of the parts of the flower which are green in most blossoms, are scarlet as a cardinal’s robe in this. If we glance at a flower stalk, we see that at its tip it looks like a braided, flattened cone; this appearance is caused by the scarlet, long-pointed bracts, each of which covers, with its bulging base, the scarlet calyx which in turn enfolds the scarlet flower bud. These bracts fall as the flowers are ready to open, making a brilliant carpet about the plant. Each flower stem continues to develop buds at its tip for a long season; and this, taken together with its scarlet bracts and flowers, renders the salvia a thing of beauty in our gardens, and makes it cry aloud to pollen-carriers that here, even in late autumn, there is plenty of nectar.