A FLOWER
TYPE: NASTURTIUM
I
Teacher and pupils visit the nasturtium bed, where the flowers stand up boldly, surrounded by the shield-shaped leaves. A search for the young flower buds and for the very old flowers leads to the discovery that these are snugly sheltered under the shields.
The greenish-yellow calyx, which is closely wrapped around the bud, is next examined. Its name is given, and its use as a protector is discussed.
The strong seed cases are opened and the seeds are discovered. The pupils are instructed to watch the insects that visit the bright flowers. Name the insects. Describe their movements. Catch a few and find the yellow powder on their furry little bodies and legs.
II
Each member of the class brings a flower to the school-room. The varieties of colours of the flowers are discussed. The cave-like form of each flower is noted. The velvety feeling of the corolla and the delicate perfume are likewise sensed by the pupils.
The pupils nip off the point of the cave and taste the nectar (honey), and thus learn why the insects visit the flowers. They next trace the course of the coloured lines on the corolla and find that they all point into the cave.
Continuing their explorations of the mouth of the cave, the pupils will discover the little boxes containing the yellow powder that the flower dusts upon the insects. The names pollen and pollen boxes are given.
The fringe on the edges of the leaves of the corolla for the purpose of preventing the insects stealing into the cave without receiving their baptism of pollen, is discovered.
The teacher should, at this point, give a brief explanation of the valuable work done by the insects in carrying pollen to cause seeds to grow in the next flower that the insect visits. The position of the tiny brush (stigma, but do not give this name) held up by the seed case for rubbing the pollen off the insect, should also be observed.
Summary.—Name and point out the parts of the flower (calyx, corolla, pollen boxes, seed cases).
What useful work do insects do for the flower?
What reward do they receive for their work?
What advertisements do the flowers put out for attracting themselves? (Bright colours, sweet perfumes, and honey)
Flowers suitable for lessons in Form II are nasturtium, larkspur, snap-dragon, morning-glory, and sweet-pea.
Note.—Botanical names should be reduced to a minimum.