lO BACTERIA, YEASTS, AND MOLDS 



Botanists class all colorless plants under one general 

 group, which they call Fungi. Under this group is a large 

 variety of plants which show wide differences of structure 

 in size and general appearance. But inasmuch as they 

 all agree in lacking green coloring material, they are, at 

 least from the standpoint of their relations in nature, prop- 

 erly placed in one general class. The group of fungi as 

 recognized by botanists is subdivided into a number of 

 divisions. A method of dividing them, convenient for 

 our purposes, is as follows. 



Fungi 



Higher Fungi. This includes the forms of large size, 

 known generally as mushrooms, toadstools, wood fungi^ 

 rusts, smuts, etc. With these plants we are not particu- 

 larly concerned in the household. 



Molds. Fungi of considerable size, easily visible to the 

 naked eye, composed of threads. 



Yeasts. Microscopic plants which multiply by a pro- 

 cess called budding, composed of oval bodies. 



Bacteria. Still smaller plants that multiply by a pro- 

 cess called fission, composed of spherical, rod-shaped, or 

 spiral bodies. 



This classification is not scientifically accurate. The 

 higher fungi include a large number of different types 

 classed by botanists into many subdivisions. But since 

 they are not concerned in household problems we may 

 most conveniently group them together and consider them 

 no further. 



The group of molds also is not a proper scientific divi- 

 sion, since under this head are included several different 



