CHAPTER XXVIII. 



FUNGI. 

 GENERAL CHARACTERS; MOLDS; MILDEWS. 



411. 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 (see paragraphs 176, 180). 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 XVI). In defining the 

 structural elements of the fungi it is convenient to speak of two 

 parts: first, the vegetative or growing part, and second, the fruit- 

 ing 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 illus- 

 tration, 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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