CHAPTER V. 



On the Structural Anatomy of Fungi. 



In order to comprehend the classified arrangement of Fangi into 

 orders and genera, and to enable anyone to understand descriptive 

 terms, and by the help of them learn how to identify species, it 

 is necessary to become acquainted with the form and structure of 

 Fungi, and with that of the several organs and parts of an indi- 

 vidual fungus. The student is recommended to familiarize him- 

 self with all varieties of these plants that come in his way, until 

 he is master of the expositions set forth in this chapter. After 

 that he will find classification no difficult task. 



To denominate terrestrial Fungi " fruits of the earth " is not 

 altogether fanciful. If we dig up the soil about the base of a 

 mushroom, or if we examine the structure upon which parasitic 

 kinds are growing, we shall find what appears to be a quantity of 

 white mould, or of little delicate threads. This matter is called the 

 Mycelium, or " spawn," of the plant, and actually constitutes its 

 vegetative tissue, being thus analogous to the roots, branches, and 

 foliage of herbaceous plants. From this Mycelium the mushroom 

 is thrown up, it being the organ which develops the reproductive 

 cells. The office of a mushroom is therefore analogous to that of 

 a fruit. In description, however, it is convenient to speak of the 

 mushroom as if it were the whole plant in itself. 



Fungi of different orders possess various features, and are not 

 all provided with the same parts or organs. The greater number 

 of mushrooms possess a Hymenophore. This is a cellular or fila- 

 mentous structure, comprehending the substance of the mush- 

 room. It may either be borne upon a stem, distinct from it, or 

 may include the whole apparent bulk of the plant. Upon the 

 surface of either the whole or a part of the Hymenophore is 

 spread the Hymenium, which is the fructifying or spore-bearing 



organ of the fungus. In the orders Agaricini, Hydnei, Polyporei, 



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