Chapter I. 



Fungi. Nutrition. 



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What the fungi are. As understood today, the plants known 

 as fungi do not include the bacteria and the slime molds. The 

 bacteria are plants which find their closest affinities with the 

 blue-green algae. Slime-molds possess fructifications which 

 have at least great superficial resemblance to those of the fungi, 

 but their vegetative life is similar to that of the lowest order of 

 animals. They are therefore known appropriately as fungus- 

 animals. 



The fungi are all devoid of leaf-green. They hold this char- 

 acter in common with bacteria, slime-molds and many flower- 

 ing plants. The lack of leaf-green is the result of a different 

 habit and nutrition method from that of leaf-green-bearing 

 plants. The latter can utilize constituents of the air and water, 

 together with mineral salts from the soil, and build them up. 

 with the power of sunlight, first into starch and then into the 

 more complex substance known as protoplasm or living sub- 

 stance. The loss of leaf-green indicates that a plant has no 

 longer any use for a starch-forming apparatus, but since it still 

 needs starch it must obtain such material in a manufactured 

 condition. Fungi are therefore dependent upon other plants or 

 animals or upon the products of these organisms for food. Al- 

 though lack of leaf-green is not characteristic of fungi alone 

 but is shared by certain other plants or groups of plants, we find 

 that the fungi do possess a distinguishing mark in the structure 

 of the vegetative portion of their bodies. 



That portion of the plant which is concerned with the build- 

 ing up of the individual plant itself is known as the vegetative 

 portion, while that which is concerned with the production of 

 cells for the development of offspring is reproductive. The 

 vegetative portion of a fungus is known as a mycelium and has 



