EXCRETION OF MATTER FROM THE BODY 419 



It is oxidised into indoxyl thus 



OH 



This when linked to sulphate of potassium forms indoxyl- 

 sulphate of potassium or indiean. 



C H 



O.S0 2 OK 



From skatol, which is methyl-indol, skatoxyl-sulphate of 

 potassium is formed in the same way. 



These bodies are colourless, but when oxidised they yield 

 pigments indiean yielding . indigo blue, skatoxyl-sulphate of 

 potassium yielding a rose colour. 



Phenol 



, H 



This is also linked to sulphate of potassium 



, -0-S0 2 OK 



and excreted in the urine. 



