50 KozLOWSKi : Primary Synthesis of Proteids 



* . * 



amount does not diminish when the plant is put in a position 

 in which it cannot assimilate, as, for instance, is the case when 

 is in an atmosphere deprived of carbonic anhydride. Schimper 

 found that in such conditions proteids cannot be produced by the 

 plant ; thus the formation of these crystals cannot depend upon 

 the formation of proteids. But although the formation of proteids 

 is one of the essential functions of the leaf parenchyma, we 

 know that another process is taking place In them, and that 

 is respiration. Whether or not we accept the view that the 

 respiration of plants is essentially based upon the spontaneous 

 dissociation of proteid molecules (the intra-molecular respiration), 

 we cannot overlook the analogy between the function of carbo- 

 hydrates as respiratory material in animals and plants. 



When the assimilation goes on normally, the cellulose deposited 

 by the decomposition of the proteid molecules augments the mass 

 of the plant, while the assimilated carbohydrates are used partially 

 in the reconstruction of that molecule, partially burnt out, the same 

 as in the animal organism a product of proteids — the fat — is stored 

 up, when the animal is abundantly fed with carbohydrates. But, 

 if the production of carbohydrates is not sufficient, the material 

 produced by the proteids is burnt the same as fat is burnt in animal 

 oro-anism under the same conditions. The amount of proteids 

 decomposed by respiration, and consequently that of the oxalates 

 is nearly the same, whether assimilation takes place or not ; only 

 in the last case the growth of the plant is hindered, for the part of 

 the protein molecule deprived of nitrogen, will be oxydized into 

 up and CO2, while its part containing nitrogen will increase the 

 amount of amides, which, as is known, is really observed in such 



conditions. 



The dependence of the secondary oxalates on light and 



chlorophyl can be explained by the proteid influence of these fac- 

 tors upon the transpiration or, in other words, upon the ascension 

 of water from the soil towards the leaves, and the introduction of 

 salts of calcium in quantities necessary to bind the produced oxalic 

 acid. This dependence of the secondary oxalates upon transpiration 

 was directly proved by Schimper*; the independence of the primary 

 ones from that function, proved by the same investigator, can be 



* Loc. cit. 89. 



