CHAPTER VI 



THE MYCETOZOA (SLIME-FUNGI) 



BADHAMIA UTEICULARIS 



In damp woods the trunks of old and decaying trees, 

 especially elm-trees, are often seen to be infested with a 

 greyish yellow parasitic fungus Stereum hirsutum projecting 

 like a shelf from the surface of the bark. Similar fungi may 

 be found on fallen trees, damp, decaying timber, old garden 

 seats or arbours, and other such places. A search under the 

 bark or on the surface of such timber will generally reveal the 

 presence of a bright yellow slimy substance spreading over the 

 surface of the wood or beneath the bark. This yellow gelatinous 

 and shapeless mass is the plasmodium of Badhamia, and the 

 Stereum is its food. If a mass of the bright yellow slime be 

 carefully removed, whilst still attached to the wood or to a 

 piece of Stereum, and kept in a dry place, it loses its slimy 

 character, dries up, and forms a thin yellow incrustation which 

 can be chipped off in flakes resembling so much yellow sealing 

 wax. This dry condition of the Mycetozoon is known as the 

 sclerotium. The protoplasm is not dead, but has simply 

 passed into a resting or encysted condition, enabling it to 

 withstand prolonged drought. Pieces of the sclerotium of 

 Badhamia which have been kept for as long as three years 

 may be revived by being brought into a moist chamber. 

 Examination shows that the sclerotium is formed of a number 

 of cysts or chambers, separated from one another by firm 

 partition walls, each cyst containing some ten or twenty nuclei. 

 If a piece of sclerotium be soaked in water for about twelve 

 hours and then placed on a moist surface (wet blotting paper 

 placed under a bell jar serves very well for the purpose) it will 

 gradually revive and pass again into the plasmodium stage. 

 The opaque horny walls of the cysts become soft and semi- 



147' 



Digitized by Microsoft® 



