Report on the Bacteriology of Water. 



365 



jntinued. 



and quite visible to the unaided eye, the larger ones opening out 

 and swarming vigorously as liquefaction began. A greenish shim- 

 mer showed where the colonies were very dense. In sixty-four hours 

 the colonies were running together, and liquefying rapidly, and in 

 eighty-six hours the whole gelatine was liquid and watery. 



The plate from the insolated tube, treated in exactly the same 

 way, showed no trace of colonies in forty hours, and only one or two 

 minute colonies, invisible to the unaided eye, could be detected under 

 the microscope in sixty-four hours. Even after seven days the 

 morula-like, dense, granular colonies only showed traces of opening 

 out and the first beginnings of liquefaction. 



Of the stab-cultures, that from the covered tube showed the 

 beginnings of growth in forty hours, and had formed a thistle-head 

 funnel of liquefaction in sixty-four hours, which rapidly extended 

 in eighty-eight hours. 



That from the insolated tube, on the contrary, showed no trace 

 of growth in forty hours, or even in sixty-four hours to eighty-eight 

 hours. 



Of coarse it may be objected that the difference here was entirely 

 due to the stab-infection having carried in so few living germs in 

 the latter case ; but to this it must be replied, that the plates show 



2 c 2 



