DISPERSAL BY WIND. 



819 



offshoots exclusively. The detachment takes place in different ways in these 

 "viviparous" Grasses. Usually the sprouts loosen from the erect panicles of the 



Fig 452. Polygohum viviparum. 



swaying haulm, and are scattered by the wind, but sometimes the separation does not 

 occur until the stem is bent down to the ground with the weight of the crowded 

 offshoote in the panicle. In this case the offshoots strike root where the pamcle 



