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Kie hypothesis that the formation of the anthocyanine compoimd is re- 

 lated to the phenomena of oxidation fotmd much support in the works of Mirande, 

 Molliard (ll) , Miss ITheldale (H) , V. Grafe (U, 5), Combes (2), etc., and was 

 applied latterly in a particiila.r manner by Palladin (ik) . According to this 

 author, there exists in all plants chromogens and oxidases. The oxidases 

 settled upon the chromogens and may givs origin to anthocyanine pigments, and 

 these may breakup by the dimlrution of the process of ^xidation and by the 

 acceleration of the processes of reduction. 



More recent research led Palladin (I3) to admit the existence of com- 

 pounds to which he gave the name prochromogens and from which, through the 

 intervention, of an enzyme, there Blight be derived a chromogen. These latter 

 may be produced in large numbers when the functional activity is more intense, 

 namely, in the spring, while during a great part of the growth period they 

 may form in small quantities by completing the process of oxidation. 



With respect to the relation which exists between the anthocyanine and 

 sugars, the research of Overton (12), which vna-s fully confirmed by that of 

 Molliard (lO) and Palladin, revealed the existence in some plants of a direct 

 relation between the production of anthocyanine and the accumulation in their 

 tissues of sugars resulting from culture. 



Finally, CombesQ), following on his research on gaseous changes during 

 the formation and disappearance of anthocyanj.© ' pigments, was led to consider 

 these substances as glucoside compounds, which originated in a more oxidizable 

 ambient or fluid than that normally present and is not differentiated from 

 that which forms under ordinary conditions according to their stage of more 

 advanced oxidation. This point of view conforms with the opinion maintained 

 for a long time by many authors, namely, that the anthocyanic oompotuids are 

 to be considered as glucosides, an opinion which found new confirmation in the 

 recent researches of Portheim and Scholl (16) , and in those of V. Grafe(i±, 5)' 



