VITALITY OF PUTREFACTIVE ORGANISMS. 161 



ing an astounding development in the hlack-fungus infu- 

 sion. Patches of moss-like matter would appear here 

 and there in the field of the microscope ; and it was no 

 uncommon thing to see from ten to twenty monads 

 nestling and quivering in tliis 'moss,' and darting 

 actively in and out of it. They put me in mind of 

 frogs amid their spawn ; and as I looked at them my 

 belief in the animality of the one was almost as strong 

 as in that of the other. Almost every patch of spawn- 

 like matter had its colony. In some cases hardly any 

 thing but monads was to be seen ; but in others the 

 crowding of active Vibrios was so great that the monads 

 wholly retreated from the field. 



§ 10. Infusions of Cucumber, Beetroot, &e. 



The fungi having disappeared on the approach of 

 winter, I turned to cucumber and beetroot, not expecting 

 that their sterilization would offer any difficulty. Two 

 closed chambers were accordingly prepared, left for the 

 proper time in quietness, and on the 7th of November 

 were charged, the one with the cucumber- and the other 

 with the beet-root infusion. In a few days the infu- 

 sions in both chambers broke down, first losing their 

 transparency and afterwards loading themselves with 

 fatty scum. Thus perplexities accumulated. 



On the 1 8th of November twenty-four Cohn's tubes^ 

 were charged with infusions of cucumber, beetroot, par- 

 snep, and turnip, six tubes being devoted to each infu- 

 sion. They were placed in a vessel of cold water, raised 

 gradually to the boiling-point, and maintained at the 

 boiling temperature for ten minutes. Before their re- 

 moval from the hot liquid they were one and all plugged 

 with cotton-wool. 



' See § 4. 



