CHAPTER XXVI. 

 FUNGI. 



GENERAL CHARACTERS; MOLDS; MILDEWS. 



395. General characters. The fungi are plants of a low 

 grade of organization, in this respect resembling the algae. In 

 fact they stand as a parallel group. The plant body, or thallus, 

 of the lower and higher forms in structure is very much like that 

 of many of the algae, and some of the methods of reproduction are 

 very similar to methods of reproduction in some of the algae. 

 There are, however, some features of structure and methods of 

 nutrition in which they differ strikingly from the algae. First. The 

 fungi are entirely devoid of chlorophyll as well as the bodies 

 (plastids) which are the basis of the chlorophyll bodies. Second. 

 Not having chlorophyll, photosynthesis does not take place, and 

 they cannot make their own carbohydrate food, i.e., the sugar and 

 starch. They are dependent on chlorophyll-bearing plants for 

 this food, just as animals are. Third. They live chiefly on organic 

 matter, either dead or living plants or animals, or their remains. 

 The fungi according to their method of nutrition can be grouped 

 in two categories: first, Saprophytes, which live on dead or 

 decaying organic matter (plants and animals); second, Parasites, 

 which live upon, or in, living plants and animals (see Chapter 

 XV). In defining the structural elements of the fungi it is con- 

 venient to speak of two parts: first, the vegetative or growing 

 part, and second, the fruiting or reproductive part. 



To THE TEACHER. At least three types of the fungi should be studied, 

 one of the molds (Mucor or Rhizopus), a powdery mildew (Microsphaera), 

 and a mushroom. Other examples in each class of the Fungi can be used 

 as illustration, or where more time can be given to the practical work the 

 teacher can select suitable examples from those described in the text. One 

 lichen should also be studied. 



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