VITALITY OF PUTEEFACTIVE ORGANISMS. 159 



however, substituted for the black one used in the 

 former experiments. On the 1st of November the 

 three infusions were very carefully introduced into 

 three chambers, a chamber being devoted to each in- 

 fusion, I thought it advisable to vary the period of 

 subsequent boiling. One tube of the yellow fungus was 

 therefore boiled for five, one for ten, and one for fifteen 

 minutes; but as it was difficult to save the infusion 

 from waste when the boiling was long continued, one 

 tube of each of the other two infusions was boiled for 

 five minutes, and the other two for ten. Tubes charged 

 with the respective infusions were exposed at the same 

 time to the common air. 



In two days the outside tubes containing the red- 

 and yellow-fungus infusion became turbid and covered 

 with the fatty scum so prevalent in our laboratory this 

 year. No scum had formed on the surface of the ex- 

 posed tree-fungus infusion, which, to casual observation, 

 appeared quite black. Closer scrutiny, however, showed 

 that it transmitted the deepest red of the spectrum, and 

 was apparently quite free from floating matter. It 

 changed rapidly during the night of the 3rd, and on the 

 morning of the 4fch of November the bottom of this 

 tube was found laden with a heavy dark-brown precipi 

 tate, while numerous dark-brown floeculi floated in the 

 liquid overhead, which had become almost as clear and 

 colourless as water. Under the microscope the dark- 

 brown mass resolved itself into confused moss-like 

 patches and long cylindrical sheaths dotted throughout 

 with small dark specks. These filaments with spore- 

 like specks have been of very firequent occurrence in 

 this inquiry. 



The deportment of the closed chambers was as fol- 

 lows :— 1. Yellow fungus : the liquid in the three tubes 

 remained perfectly and permanently clear and without 



