Page:Popular Science Monthly Volume 19.djvu/379

Rh tend to drive the seed into the ground. If, then, the air becomes drier, the awn will again roll up, in which action M. Roux thought it would tend to draw up the seed, but from the position of the hairs the feathery awn can easily slip downward, and would therefore not affect



the seed. When moistened once more, it would again force the seed farther downward, and so on until the proper depth was obtained. A species of anemone (A. montana) again, has essentially the same arrangement, though belonging to a widely separated order.