278 FUNGI. 



(134) White Agaric. 



White or larch agaric is the fungus, Potyporus officinalis, 

 Fries (sub-class Basidiomycetes). 



It is found in masses varying in size from that of the fist to 

 that of a child's head. Externally it is reddish or yellowish ; 

 internally, white and spongy. The outer portion is often 

 removed, and the remainder cut up into smaller, irregular 

 pieces. 



The tissue of which it is composed consists of a mass of 

 loosely agglomerated, interlacing tubular hyphae, which may 

 often be rendered more easily visible by gently warming the 

 preparation in acetic acid. Accompanying the hyphse are 

 crystals of calcium ozalate, small calcareous masses of varying 

 size and irregular shape and numerous minute spores. 



The diagnostic characters of powdered white agaric are : 



(a) The interlacing tubular hyphce. 



(b) The presence of calcium oxalate. 



(c) The presence of spares. 



