128 KANSAS ACADEMY OF SCIENCE. 



Oct. 31, 12 m., examined drop of the turbid fluid with microscope 



and found it to be swarming with bacteria. 

 Beaker No. 31: Containing two Sternberg flasks, one of sterilized hay infusion, 



one of sterilized turnip infusion, charged October 30. 

 Nov. 4, 3 p. m., inoculated each flask with a few drops of filtered 



Pasteur solution. 

 Nov. 5, 3 p.m., clear; no change. 

 Nov. 10, 2 p. m., clear ; but the turnip flask containing small 



patches of mould. 

 Nov. 15, 12:30 p.m., clear; the mould in turnip flask not growing 



much. 

 Nov. 24, 3 p. m., clear, but considerable white mould in turnip flask. 

 Beaker No. 32: Containing two flasks, same as No. 31. 



Nov. 4, 3 p. m., inoculated each flask with small quantity of unfil- 



tered Pasteur solution containing bacteria. 

 Nov. 5, 3 p. m., both flasks turbid; the turnip milky, the hay hazy. 

 Nov. 10, 2 p.m., the hay-flask clearing; a white sediment in bottom 



of flask; the turnip turbid, with a little sediment. 

 Nov. 15, 12:30 p.m., turnip-flask milky; the hay rather clear, with 



sediment at bottom. 

 Nov. 24, 3 p. m., turnip turbid, with sediment; the hay clear, with 



sediment. 

 Tube No. 33: Charged Nov. 4, 3 p. m., with filtered Pasteur solution; clear. 



Loosely plugged with cotton. 

 Nov. 5, 3 p. m., perfectly clear. 

 Nov. 10, 2 p. m., slightly turbid. 

 Nov. 24, 3 p. m., turbid. 

 Tube No. 34: Charged same as No. 33. 



Nov. 5, 3 p. m., perfectly clear. 

 Nov. 10, 2 p. m., slightly turbid. 

 Nov. 24, 3 p. m.. turbid. 



SUMMAEY. 



The culture tubes were kept from Oct. 30, 12:30 p. m., to Nov. 4, 9 a.m., before 

 any inoculations were made. They seemed to be free from bacteria at this time. 

 The sterilization and protection from attack by floating germs seemed to be per- 

 fect. Tubes 8, 10, 15 and 16, not inoculated, are to-day ( Nov. 23) as clear as when 

 charged. Nor is this due to lack of nutrition in the culture fluids; for tubes G, 9, 12 

 and 14, inoculated with solutions containing bacteria, became turbid within 24 to 30 

 hours. And tubes 25, 26 and 27 (turnip), left exposed to the quiet air of the room, 

 became turbid within a few days. The behavior of tubes 22 and 23 (hay), exposed 

 to the same air, is quite inexplicable to us. This hay infusion furnished pabulum 

 for the motile bacteria thrust into it by inoculation, but the dry bacterial and peni- 

 cillial spores floating in the air were not able to germinate in it. The infusions in 

 the flasks show this same readiness to furnish pabulum for introduced bacteria (see 

 flasks in beaker 32), and show the infusions to have been perfectly sterilized, and 

 no bacteria appear in those flasks not inoculated (see flasks in beakers 19 and 20). 



It is fair to presume that if any motile bacteria penetrated the walls of the 

 earthenware filter, that the inoculation of these culture tubes with the filtered 

 liquids would be followed by the appearance of bacteria (perceived by films or tur- 

 bidity) in the tubes. The notes on tubes 4, 5, 7, 11, 13, 17, and flasks 7a, 13a, and 

 those in beaker 31, indicate a very effective restraining action by the filter. The 



