Page:An introduction to physiological and systematical botany (1st edition).djvu/333

 Rh though sometimes it is barbed, or at least its covering, as in Stipa, ''Engl. Bot. t.'' 1356, that it may not easily be withdrawn again by the powerful feathery appendage of that plant, which after having by its circumvolutions forced the seed deeper and deeper, breaks off at a joint, and flies away.

The various modes by which seeds are dispersed cannot fail to strike an observing mind with admiration. Who has not listened in a calm and sunny day to the crackling of Furze bushes, caused by the explosion of their little elastic pods; nor watched the down of innumerable seeds floating on the summer breeze, till they are overtaken by a shower, which moistening their wings stops their further flight, and at the same time accomplishes its final purpose, by immediately promoting the germination of each seed in the moist earth? How little are children aware, as they blow away the seeds of Dandelion, or stick Burs in sport upon each other's clothes, that they are fulfilling one of the great ends of Nature! Sometimes the Calyx, beset with hooks, forms the bur, as in