NUTRITION 



entire organism is merely a globular bluish-green granule 

 of plasm. Moreover, in the simplest forms of nucleated 

 primitive plants {algarice) — many of the so-called uni- 

 cellular algae — the metabolism is effected by a single 

 grain of chlorophyll. There is usually a large number 

 of them in the plasm of the plant-cells. 



Another kind of plasm-synthesis, quite different from 

 the ordinary plasmodomism by chlorophyll and sunlight 

 has lately been discovered in some of the lowest organ- 

 isms (by Heraeus, Winogradsky, and others). The nitro- 

 bacteria (or nitromonades) are tiny monera (unnucle- 

 ated cells) that live in complete darkness underground. 

 Their globular colorless plasma-bodies contain neither 

 chlorophyll nor nucleus. They have the remarkable 

 capacity of forming carbo-hydrates, and from these 

 plasm, by a peculiar synthesis out of purely inorganic 

 compounds — water, carbonic acid, ammonia, and nitric 

 acid. Pfeffer has called this carbon-assimilation, on 

 account of its purely chemical nature, "chemosyn- 

 thesis," in opposition to the ordinary photosynthesis by 

 means of sunlight. There are also other bacteria 

 (sulphur- bacteria, purple - bacteria, etc.) that show 

 various peculiarities of metabolism. The nitro-bacteria 

 must belong to the oldest monera, and represent a 

 transition from the vegetal chromacea to the animal 

 bacteria. 



The extensive class of the fungi (or mycetes) resembles 

 a part of the bacteria in regard to metabolism. These 

 organisms are, it is true, generally regarded as plants, 

 but they have not the capacity of the green, chlorophyll- 

 bearing plants to supply themselves with carbon from 

 the carbonic acid in the atmosphere. They have to take 

 it from organic substances, such as albumin, carbo- 

 hydrates, etc., like the animals. But while the animals 

 have to derive their nitrogen from the latter, the fungi 

 can obtain it from inorganic matter in the earth. Fungi 



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