38 



upon the spore walls, thus creating some disturbance in 

 physico-chemical equilibritim which is subsequently prop- 

 agated inward, is a question for the answering of which 

 no evidence is yet at hand. Nevertheless, the present 

 studies have clearly demonstrated that the presence of 

 Cu(N03)2 alone in the medium inhibits germination if the 

 concentration be above a very low limit, produces markedly 

 altered forms of renewed activity if the concentration is 

 somewhat lower, and allows normal germination only when 

 the solution is exceedingly dilute. While these facts must 

 be interpreted to mean that the copper salt tends to upset 

 the protoplasmic system in some way and that it is possible 

 for that system to be so disturbed as either to inhibit 

 germination absolutely or to allow the process to proceed 

 in modified form, yet much more direct evidence of proto- 

 plasmic disturbance was frequently met with in the progress 

 of this work. Spores which had been prevented from any ger- 

 minational activity by the presence of CuCNCglg frequently 

 possessed a characteristic coarsely granular appearance, 

 as though a precipitate or coagulum had been formed within 

 the protoplasm. Furthermore, this same appearance was often 

 encountered in spores which exhibited modified germination 

 under the influence of copper. From this it appears that 

 the granular appearance of the protoplasm does not necess - 

 arily denote death, but to settle this point conclusively 

 and to determine whether the production of granulation 



