2 1. NAGAI : 



3. An Interpretation of the Kesnlts. 

 i. Discussion. 

 ID. Svimmary and Conclusion. 

 Explanation of the Plate. 



Postscript. 



Introduction. 



The workers in genetics have established the fact that in certain cases 

 the formation of authocyanin pigments is caused by the interaction of a number 

 of definite pigment yielding components which are retained by the separate 

 genetic factore. Neither of these components has the power to produce the 

 pigment unless the complete system is established by their union. We owe 

 much to the Labours of Bateson, Püxnett, Miss Sad^-dees, Miss Wheldale, 

 Bam- and many othei-s on the part of genetics/ and WiLLSTÄrrEE and his 

 collaborators in the field of chemistry who have shown for the first time, the 

 exnct chemical constitution and the inten-elationship of the colijming mattei-s' 

 concerned. 



The present paper deals with the result of an investigation carried out 

 in order to discover what rehitiou exists between anthocyauin and brown 

 pigments both of wliich occm- widely in the plant Idngdom and what obser- 

 vation can be made with regaixl to the physiological action of the genes which 

 are analysed by the breeding experiments for the characters in which those 

 pigments are concerned. 



I. Physiological Study. 



1. The Action of Oxidizing Enzymes on Anthocyanins. 



If we accept the view that anthocj-anins are formed by the oxidation of 

 flavone instead of by reduction, and the oxidizing enzymes play an essential 

 part in this change in the hving plant cells, it is uecessai-y to offer the direct 

 evidence to lend support to the xiavr. 



When an alcoholic 'or aqueous exti-act of authocyanin which is sHghtly 



1. See Wheidale, M., Anthooyanin Pigments ot Plants. 1916. 



2. See Pebkis, G. A., and Everest. .\. E , The Natural Organic Colouring Matters. 1918. 



