SOME MYXOMYCETES OF ECONOMIC IMPORTANCE 339 



After the spores are mature, the wall of the sporangium breaks 

 open and the spores are scattered far and near by wind, animals, 

 and other agencies. When the spores fall on a suitable object 

 and conditions are right, the protoplasm breaks out of the heavy 

 wall and either grows directly into a new plasmodium, or pro- 

 duces cilia, swims about 3 and multiplies like the simple one-celled 

 forms of animals (Fig. 291), the plasmodium being formed later 

 by the fusion of these animal-like bodies. 



Some Myxomycetes of Economic Importance 



Most of the Myxomycetes are saprophytes and consequently 

 the group is not so important economically as the Bacteria and 

 Fungi. Of course the saprophytic forms are of some importance 



FIG. 292. Cabbage plants attacked by the Club Root Myxomycete 

 (Plasmodiophora Brassicae) which causes wart-like distortions. From Woronin. 



because they disintegrate organic matter and make it soluble, so 

 that it can soak into the soil and be used by higher plants. 

 There are, however, a few parasitic forms which attack some of 

 our useful plants and cause considerable trouble and loss. 



