XIV 



CONTENTS 



Relationship between catechol tannins and flavonols, etc. 

 Fxonomic uses of tannins ....... 



Composition of certain dye-woods and barks and their extracts 



Old fustic 



Jack wood 



Quercitron bark 

 Depsides 



Lecanoric acid 

 Evernic acid . 

 Chlorogenic acid 



Properties 



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SECTION VI.— PIGMENTS 



Chlorophyll . 



Constitution . 



Action of acid and alkali on chlorophyll 

 Action of alkalis 

 Action of acids 

 Crystalline and amorphous chlorophyll . 

 Relationship between chlorophyll and haemoglobin 

 Extraction of chlorophyll .... 

 Carotinoids or yellow pigments accompanying chlorophyll 



Carotin 



Lycopin 



Xanthophyll . 



Rhodoxanthin 



Fucoxanthin . 

 Anthoxanthins 



Flavones and xanthones 



Yellow colouring matters derived from flavone 



Yellow colouring matters derived from xanthone 

 Properties of anthoxanthins 

 Anthocyanins .... 



Occurrence, conditions of formation and physiological 

 significance 



Preparation and properties 

 Reactions and properties 



Chemical constitution 



The colour of petals 

 Connection between anthocyanins and anthoxanthins 

 Phycoerythrin 



Preparation 



Reactions 

 Phycophaein 

 Phycocyamn 



Preparation 



SECTION VII.— NITROGEN BASES 



Alkaloids 



Occurrence 



Classification 



General properties 



General reactions 



Isolation 



Origin of alkaloids in the 

 Ptomaines . 

 Purine bases 



Physiological significance 

 Nucleic acids 



Hydrolj'tic products 



plant 



of nitrogen bases 



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