Lesson CLVIII

The Bee-larkspur

Leading thought—The bee-larkspur begins blossoming early in the season, the blossom stalk elongating and developing new buds at its tip until late in autumn. The flower has a very interesting way of making the bees carry its pollen.

Method—Bring to the schoolroom a flower stalk of the bee-larkspur, and there study the structure and mechanism of the flower. This lesson should inspire the pupils to observe for themselves the visiting bees and the maturing seeds. Ask them to write an account of a bumblebee making morning calls on the larkspurs.

Observations—1. Which flowers of the larkspur open first—those near the tip of the stem or those below?

2. Examine the buds toward the tip of the flower stalk. What color are the sepals in these buds? Do the sepals change color as the flower opens? Note the little green knobs which tip the closed sepals that clasp the bud. What color are the sepals on the open flower? Is there any green upon them when open?

3. Where is the nectar-spur? Which sepal forms this? How are the other sepals arranged?

4. Now that we know the flower gets its brilliant color from its sepals, let us find the petals. Look straight into the flower, and note what forms the contrasting color of the heart of the flower; these are the petals. Can you see that two are joined above the opening into the nectar-tube? How many guard the entrance from below? How are these lower petals hinged about the upper one? Peel a sepal-cover from the nectar-spur, and see if the upper petals extend back within the spur, forming nectar-tubes.

5. Take a flower just opened, and describe what you see below the petals. What is the color of the anthers? Of the filaments? Can you see the stigma?

6. Take a flower farther down the stalk, which has therefore been open longer, and describe the position of the anthers in this. Are there any of them standing upright? Are they discharging their pollen? What color is the pollen? Are these upright anthers in the way of the bee, when she thrusts her tongue into the nectar-tube?

7. Take the oldest flower you can find. What has happened to the anthers? Can you see the pistils in this? In what position now are the stigmas?

8. Push aside the anthers in a freshly opened flower and see if you can find the stigmas. What is their position? How do they change in form and position after the pollen is shed? Do they arise in the path of the bee before all the pollen from the anthers of their own flower is shed? If so, how are they pollenated?

9. Suggestions for Observation in the Garden—Watch a bumblebee working on the larkspur and answer the following questions: How does she hold on to the flower? Where does she thrust her tongue? Can she get the nectar without brushing the pollen from the anthers which are lifting up at the opening of the nectar-tube? In probing the older flowers, how would she come in contact with the lifted stigmas? How do the petals contrast in color with the sepals? Does this tell the bees where to look for nectar? Compare the common larkspur with the bee-larkspur, and notice the likeness and difference. What kind of fruit capsules has the bee-larkspur? Describe the seeds, and how they are scattered.