The Non-Green Plants 



379 



W. S. Cooper 

 Fig. 239. The dodder (Cuscuta), a yellow parasite belonging to the morning-glory family, 

 grows on other plants not only in moist regions, but also in the arid coastal region of Cali- 

 fornia. It is here shown growing on Abronia. 



Some small non-green plants, however, secure their energy, 

 not from organic substances, but by oxidizing inorganic salts. 

 The most important of these are the nitrifying bacteria in the 

 soil that oxidize ammonia and nitrites to nitrates in their respira- 

 tory processes. With the energy thus secured they construct 

 carbohydrates, fats, proteins, and organic compounds. These 

 plants are autophytes as truly as the green plants. They live 

 in the soil independent of other plants, and they can grow without 

 organic compounds. Another group of bacteria common in 

 sewage-polluted water is able to secure energy through the 

 oxidation of inorganic sulfur compounds. 



Vital syntheses. In this connection it may be noted that 

 living organisms differ greatly in their synthetic powers. The 

 green plant using the energy of the light in the first processes 

 can build everything that it requires. Colorless plants, if given 

 sugar or other carbohydrates that they can use, can construct 

 fats and proteins, and, as we have seen, some of the bacteria 



