CHAPTEE IX 



CONSTITUENTS 



The chemical composition of Fungi varies considerably as to 

 quantitative proportions in different families, and, to a less 

 extent, in different genera and species. The larger Fungi, which 

 constitute the Hymenomycetes, are those which have generally 

 been submitted to analysis. Of course water is a considerable 

 element in fresh specimens of fleshy Fungi. The highest per- 

 centage is about 9 per cent, and the lowest about 9 per cent, 

 the latter being that of a woody Polyporus. Perhaps a reason- 

 able mean for Agarics would be about 60 or 70 per cent.^ 

 Taci gives the following analysis of Eussula foetens : — 



Water 



Maimite 



Fibrin (Albuminoids^ 



Gum 



Fungin or Cellulose 



Fat . 



Ash 



67-0 



0-G 



4-6 



1-5 

 20-0 



0-68 



5-13 



99-51 



Acids, etc. undetermined. 



The substances allied to sugar are mannite and trehalose, 

 the latter found in ergot, and elsewhere. Albuminoids are 

 some form of fibrin or albumen, and distinguished by containing 

 nitrogen as well as carbon, hydrogen, and oxygen. These 

 substances are valuable as food, the nutritive value being in 

 great part indicated by the percentage of nitrogen. This per- 

 centage is high in Fungi, higher in dried Agarics than in peas 



1 Fistidiiia licpaiica contains 86 per cent of water. 



