84 



SEEDS AND FEUITS 



Seeds and Fruits Carried by Water. — Plants, such as the 

 Great Ragweed, Smartweeds, Bindweeds, WiJlows, Poplars, and 

 Walnuts which grow along streams, have their seeds and fruits 

 floated away during overflows. Sometimes, when the banks of 



Fig. 86. — Plants of the tumble weed {AmaranthiLS alhus) tumbling over 

 the ground and scattering seeds as they go. After Bergen. 



streams cave off, plants with ripened seeds fall into the current 

 bodily and are carried for miles down the stream, finally lodging 

 in fields where their seeds grow. The seeds of plants growing on 

 the upland are washed to the lowlands during rains and seed the 

 bottom fields. Some fruits, as in case of the Coconut, are so 

 resistant to salt water that they can be carried long distances by 

 ocean currents. 



Seeds and Fruits Carried by Animals. — Birds eat the fruits 

 of some plants for the outer pulp, and the hard seeds pass, undi- 

 gested. In this way the seeds of the Nightshades, Poison Ivy, 

 Pokeweed, Blackberry, Pepper Grass, and others are distributed. 

 Even the seeds and fruits of Thistles, DandeUon, Ragweeds, and 

 Knotgrass may be eaten in such large quantities that many pass 

 undigested and start new plants wherever they fall. Birds often 

 carry sprigs of plants to places where the seeds may be eaten 

 without molestation and in this way distribute seeds. {Fig. 87.) 

 Birds that wade in the edge of ponds, lakes, and streams 

 often carry away on their feet and legs mud containing seeds. 



