FUNGI. 



I. BASIDIOMYCETES. 



AGARICUS CAMPESTRIS, /. (The Common 

 Mushroom). 



I. Examine a brick of " mushroom spawn," such as 

 is sold in the shops for the artificial culture of the 

 Mushroom (Agaricus campestris). It will be found to 

 consist of a compost of dried cows' dung, loam, and 

 clay, in which numerous very fine microscopic filaments 

 are present, or irregularly branched white bands which 

 may be easily recognised with the naked eye. This is 

 the mycelium. The best spawn is that in which the 

 mycelium is generally distributed, so as to give the 

 whole mass a uniformly grey appearance. It is to be 

 remembered that the mycelium of other Fungi may> 

 and most probably will, be present in greater or less 

 amount. 



Tease out with needles in water some of the mycelium, 

 mount in water, and examine under a low power: note 

 that the white bands recognised with the naked eye are 

 composed of numerous colourless filaments (mycelial 

 hyphse), associated together in a parallel course, while 



H 



