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Parasitic Plants. 



In the lesson on the plant's food only those plants were 

 referred to which made food for themselves out of carbonic acid 

 and water, and matters dissolved in water. Two very common 

 plants may serve as examples of those which rob other plants of 

 nutrition gathered by them, the Dodder and Mistletoe. 



Dodder. 



While hunting for examples illustrating seed-distribution, in 

 July to September, the pupils will likely come across a curious 

 parasitic plant known as Dodder. As it illustrates the life of a 

 plant without roots or leaves using those of other plants, it makes 

 an instructive lesson. 



The dodder occurs as slender leafless vines twining about the 

 stems of other plants, sending into their leaves and stems little pro- 

 cesses by which they suck the juices of the host, which supplies 

 them with their whole nourishment. This parasite relying on the 

 leaves and roots of its host has none of its own; the leaves may 

 occur as the merest rudiments. It bears flowers and these form 

 seeds. The seeds germinate in the ground. Thus, at first, the 

 plant has a root which serves its purpose until it can grow up and 

 attach itself to its host, when it discards its roots. There are dif- 

 ferent species of dodder. One very common one in the coast 

 marshes forms conspicuous orange patches of fine tangled vines. 

 Another is of pale yellow color and is found on many kinds of 

 plants more commonly growing in low, moist situations, altho 

 found sometimes in the fields and hills. These plants belong to 

 the same family to which the morning-glory 'belongs. 



Mistletoe. 



The study of the robber plant, dodder, will almost surely 

 suggest to many pupils the question of the life of the Mistletoe* 



