THE PAGE OF NATURE. 



213 



through the decaying substances on which the mushroom 

 grows. These filaments are formed of elongated colour- 

 less cells. They are developed under ground, and in 

 other plants would be called roots. This part of the 

 fungus is called by botanists mycelium, and is popularly 

 known as the spawn by which the mushroom is fre- 

 quently propagated. In favourable circumstances this 

 mycelium spreads with great rapidity, sometimes, espe- 

 cially when prevented from developing organs of repro- 



Fio. 27. PARTS OF MUSHROOM (Agaricus procerus). 



(a) Pileus or Cap. (6) Hymenium or Gills, (c) Annulus. (d) Stipe or 

 Stalk, (e) Volva. (/) Mycelium or Spawn, (g) Spores. (K) Basidia. 



duction, attaining enormous dimensions. It may be kept 

 dormant, in a dry state, for a long time, ready to grow 

 up into perfect plants when the necessary heat and mois- 

 ture are applied. When the requisite conditions are pre- 

 sent, and the mycelium begins to develop the repro- 

 ductive tissue, there is formed at first a small round 

 tubercle, in which the rudiments or miniature organs of 

 the future plant may be distinctly traced, just as the 



