QO PLANTS 



to the support by the contracting spirals. Tendrils in some 

 instances eiid in adhesive discs by which the plant is enabled to 

 cling to a smooth plane surface. Lastly, the twining climbers, 

 swaying their growing tips in a spiral around the axis of support, 

 coil themselves bodily about their host. In neither of these 

 cases does the climber obtain any nourishment from the host, 



FIG. 44. The trumpet vine, a climber. 



although the latter may be seriously handicapped or even 

 finally destroyed through shading by its vigorous yet dependent 

 hanger-on. 



213. Epiphytes constitute another class of plants which 

 depend upon others for mechanical support. They have no 



