H'J 



might not be a post mortem effect, the following experiment 

 was performed. 



Spores which had "been for 18 hours in cultures with 

 Cu(NC ) alone, at a concentration of O.OCCCSm, were employ- 

 ed. In this solution no germination has ever been found in 

 the more than twenty separate cultures which have been ob- 

 served, and the protoplasm usually appeared markedly gran- 

 ular. The spores were transferred from the Cu(N03)^ solut- 

 ion to a new drop culture with distilled water and were 

 returned to the thermostat. At the end of 24 hours observ- 

 ation showed that many of the granular spores had germinat- 

 ed normally, although the granular appearance was still 

 very noticeable. Further proof that the granulated appear- 

 ance with which we have to deal is not a post ;.-.ortem effect 

 of copper poisoning may be derived from the fact that the 

 germinal tubes of spores which had germinated in a combin- 

 ation solution of O.OCClm Cu(KC j^ and 0.0C0O6m Ca(KC3)2, 

 elongated considerably when the cultures were allowed to 

 remain in the thermostat for a second day, although the 

 spores showed the characteristic granulation. 



It seems probable from these and other similar lines 

 of evidence that the copper of the solution penetrates the 

 spore wall and gives rise to the precipitation or coagulation 

 effect just described 



