. Botany of the living plant. Botany; Plants. 326 BOTANY OF THE LIVING PLANT so that it may be conveyed to a distance before reaching the ground. In many Valerianaceae (Fig. 246) and Compositae (Fig. 247), where < the fruit is one-seeded and does not split, the calyx is persistent, and developing as the feathery pappus buoys up the inferior achene when set free, so that it may be conveyed to a distance before reaching the ground. The development of flat- tened wings upon seeds or fruits is closely analogous. Examples in the case of winged seeds are seen in the Bignoniaceae (Fig. 248), and o
. Botany of the living plant. Botany; Plants. 326 BOTANY OF THE LIVING PLANT so that it may be conveyed to a distance before reaching the ground. In many Valerianaceae (Fig. 246) and Compositae (Fig. 247), where < the fruit is one-seeded and does not split, the calyx is persistent, and developing as the feathery pappus buoys up the inferior achene when set free, so that it may be conveyed to a distance before reaching the ground. The development of flat- tened wings upon seeds or fruits is closely analogous. Examples in the case of winged seeds are seen in the Bignoniaceae (Fig. 248), and of winged fruits in the Elm, Ash or Sycamore (Fig. 249). It is note- worthy that winged seeds and fruits are most common where the plants that bear them are of some stature, or are climbers ; so that they have to fall a considerable distance. The wind has thus a chance of scatter- ing them far and wide. For large seeds a more effective means of transit is by water, which in commerce is a very efficient method for goods generally. Given a movement of water and a floating seed or fruit, dispersal is easy. The Water Lily is an example. The large berry ripens under water. It there splits, and the coherent mass of seeds, each with bubbles held in its aril, floats to the surface. There the seeds separate, drifting about till the bubbles are liberated by the decay of the aril. The seeds thus dispersed then sink. More striking examples are seen in lit- toral or estuarine plants, of which the seeds or fruits are often very large : for provided they float the size is immaterial. In Barringtonia (Myrtaceae), Scaevola (Goodeniaceae), and Heritiera (Sterculiaceae), which are all estuarine plants, the relatively large fruits have a fibrous. Fig. 247. Fruit of Dandelion, with pappus as parachute. Note the absence of bracteoles on the general Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and a
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