CALIFORNIA PLANTS IN THEIR HOMES 



a filaree fruit that has turned brown and is just ready to 

 explode, and give it a little twist. The five pistils spring 

 away from the receptacle like bits of bent whalebone, and 

 for much the same reason. As they fly off, they may be 

 caught and carried with the wind because of the long silky 

 hairs of the styles. 



Now look carefully at the seed part, or rather at the 

 brown ovary wall that contains the seed; it is tipped with 

 a little hook and is covered with bristles that slope outward 

 and upward. Put one in your sleeve and see how easily it 

 slips in, and how troublesome it is to get out. So these 

 bristles must be of great use to the seeds in keeping them 

 in the sheep's wool until they are carried a long distance. 

 The silky hairs, then, are of use when the wind is the car- 

 rier; the bristles, when the sheep serve the plant; but the 

 most interesting feature is the twisting motion that gives 

 the fruits their name of ''clocks." The clock you have 

 put in your sleeve has probably turned round several times 

 while you were reading this. I^et it finish twisting, then 

 put it in water and watch it; before long it will be per- 

 fectly straight; as it dries, it twists again, and so on. 

 Think of the use of the coiling and uncoiling to the little 

 fruits that lie in the dust on the ground through all the dry 

 season. With every dew or fog they uncoil; as the sun 

 comes out, they twist again. Do you not see that this helps 

 to bury them in the dust ? If there is moisture enough to 

 soften the soil, it makes the clocks uncoil at the same time, 

 and they will actually screw themselves into the earth; so 

 by the time the autumn rains come, our filaree seeds have 

 pretty well planted themselves; we have seen how promptly 

 they spring up after the first rain. 



The geraniums of our gardens have the same mechan- 

 ical devices for seed distribution. The pollination of their 

 flowers, too, is very interesting, and you can find out their 

 story for yourselves. Notice whether the flowers are reg- 



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