i68 TEXT-BOOK OF FUNGI 



chromogenous materials. That is to say, they contain 

 substances which, when oxidised, are transformed into 

 coloured products, and that the colours of such species as 

 Lactarius deliciosus^ Russula lepida, and Clitocybe inversa 

 are due to the oxidation of bodies which form a pigment in 

 the hyphae of the cuticle of the fungus. This explanation 

 receives support from the fact well known to all those who 

 are familiar with fungi in their native haunts, that in cases 

 where the pileus is normally coloured, those portions of 

 its surface protected from the action of the air by the 

 adhesion of a leaf remain colourless. 



The brilliant vermilion colouring matter of the Ply 

 Agaric, Amanita muscaria, has been investigated by 

 Griffiths, who calls it amanitin. It is insoluble in water, 

 soluble in chloroform and ether. Solutions give no charac- 

 teristic absorption bands in the spectroscope. 



The intense verdigris-green colour of Helotium aerugi- 

 nosum and allied species has been the subject of much 

 speculation. The subject has recently been investigated 

 by Vuillemin, who shows that the green colouring matter 

 is a product of the fungus and not an obligate parasitic 

 Bacterium, as has been suggested. It is located in masses 

 in the lumen of the hyphae, and not in the wall, and is 

 considered as a reserve substance. Liebermann has ob- 

 tained the green substance as pure crystals, and calls it 

 Xylindein. 



Finally, Prillieux states that Xylindein in a solution of 

 chloroform shows under a spectrum analysis certain rays 

 of absorption parallel with those of chlorophyll, but that 

 it does not act under the influence of light as chlorophyll 

 does. 



Nadson, a Russian chemist, has made some interesting 



