184 UNDER THE OPEN SET 



generation is sure. But to this tempta- 

 tion the poison ivy has not succumbed. It 

 still works up its own sap, and so long as it 

 does this it is probably safe from the de- 

 grading fate that has overtaken the lowly 

 dodder as a result of yielding absolutely to 

 the same tempting habit. To give it this 

 power to cling to a support, the poison ivy 

 has developed a faculty of sending out 

 abundant roots all along its stem, and then 

 clinging to anything they touch. When the 

 plant lies prostrate on the earth, these roots 

 serve as additional feeders and help it to draw 

 nourishment from the ground, even should 

 an animal, in trampling about, break off the 

 twigs from the parent stem. But when a 

 suitable opportunity comes these roots help 

 the plant to rise by serving as holdfasts. 



Then too the plant has learned to cater 

 to our blackbirds in the matter of fruit. 

 These birds are particularly fond of the 

 whitish berries which hang so tightly to the 

 stem that they may be found late in the 

 winter when fruits are scarce. Within this 

 toothsome pulp are seeds so small and hard 



