So let us look closely at some of these air ships, and try to guess their errand. I hope that some time ago you were told to get together as many different kinds as you could find, and to bring them here this morning. In this picture you see some of the air ships of the milkweed (Fig. 49). The lower part of Fig. 48 is a seedbox of the milkweed. To this are fastened the silky threads which make the sail that carries the seed through the air with the least wind, just as the canvas sail carries the boat across the water. Can you think of some other plants that send abroad seed sailboats? [Illustration: FIG. 49] Perhaps some of you remember the beautiful pink or purple flowers which grew last summer in tall spikes along the road and up the mountain side. These were borne upon a plant called sometimes fireweed and again willow herb (Fig. 50). The first name was given to it because it grows freely in places that have been laid waste by fire. The latter one it owes to its leaves, which look somewhat like those of the willow. [Illustration: FIG. 50] By the end of August most of these beautiful blossoms had disappeared, leaving in their place the fruit. This fruit of the fireweed or willow herb is a long pod such as you see in the picture (Fig. 51). This pod is packed full of seeds, to each one of which is fastened a silky sail. Finally all these pods split open, letting out their little air ships (Fig. 52), and giving a beautiful, feathery look to the great patches in which they are found. [Illustration: FIG. 51] [Illustration: FIG. 52] [Illustration: FIG. 53] [Illustration: FIG. 54] Another plant which launches air ships is the clematis. In August its pretty white blossoms clamber over the stone wall, and twist about the bushes and trees, making the lanes very lovely. In the fall this climber is almost as pretty as in summer, for its fruit clusters (Fig. 53) are made of such long-tailed seeds as you see in Fig. 54. When these open, and float away with the first light wind, you can see how well their little sails are fitted to catch the breeze. [Illustration: FIG. 55] [Illustration: FIG. 56] In October and November nearly every roadside is lined with clusters such as you see in the next picture, except that the picture cannot give their soft, velvety look. These are the fruit clusters of the golden-rod (Fig. 55), made up of quantities of silky-tailed seeds such as you see above (Fig. 56). And this is the fruit cluster of the aster (Fig. 57). Each little puffball is composed of many aster seeds (Fig. 58). [Illustration: FIG. 57] [Illustration: FIG. 58] The pasture thistle is almost as beautiful in fruit as in flower. It swells up into a great silvery cushion, which finally vanishes in a cloud of floating thistle down. And here is the fruit cluster of the dandelion (Fig. 59), and also a single seed sailboat (Fig. 60).