4:8 EASY LESSONS IN VEGETABLE BIOLOGY. 



solutions. Bacteria of different kinds are minute 

 fungi, similar to the yeast-plant, but living in solu- 

 tions of animal matter, in which their growth causes 

 putrefaction. Recent studies render it likely that the 

 more simple forms are but imperfectly developed 

 stages in the life-history of other kinds. Fig. 19 

 shows the appearance of 'bacteria when greatly mag- 

 nified. All fungi are made up of elongated cells, 

 sometimes branching and sometimes membranous or 



Fig. 19. 



pulpy, forming a mycelium, or spawn, and rounded 

 cells forming spores, or seeds, which may be supported 

 on filaments or contained in sacs. The common 

 mushroom is one of the larger fungi, and the white 

 or green mold on preserves, cheese, etc., an example 

 of the minuter kinds. 



Many diseases of plants and animals are associated 

 with the presence of fungi. Mildew and rust in 

 wheat, the potato-blight, the false membrane in diph- 

 theria, and many other evidences of diseased action, 



