55 



Nickel . Nickel nitrate proved to be very slightly 

 toxic to these fungus spores, its effect on germination 

 being manifest only in very high concentrations. Cn this 

 account no study was made of the possible influence of cal- 

 cii;mi and magnesium nitrates upon this toxicity. 



The toxic effects of NiCNCglg alone may be added 

 here. A concentration of 0.5m inhibited germination. In a 

 concentration of C.25m, nixmerous local swellings of the 

 spores were observed. Both local swellings and normal ger- 

 mination were present in a C.125m solution of this salt, 

 and germination was perfectly normal, as in the distilled 

 water control, where a concentration of O.C-Sm or lower 

 was employed. 



Germinating spores in 0.25m concentration of 

 Ni(NC2)2 frequently exhibited a granular appearance such 

 as has been describeil for spores in solutions of Cu(NC3)2 

 which were not quite concentrated enough to inhibit all 

 activity. 



