66 HISTORY AND CAUSE OF THE COCONUT BUD-EOT. 



blue did not fade out. Other experiments were made by cutting off 

 the top of the cotton plug of the inoculated tube, pushing it down 

 below the top of the tube so as to form a cavity, and then putting 

 pyrogallic acid and caustic soda into this space and sealing with 

 rubber stoppers smeared with vaseline. In 24 hours these cultures 

 also clouded. 



Ordinary stab cultures were made in fresh nutrient agar, and 

 melted vaseline was inserted with a sterile pipette to cover the agar 

 to a depth of 1 c. c. The agar eventually shrunk and left a space 

 about 3 mm. high between it and the solidified vasehne. A very 

 thin film of growth appeared on the surface of the agar and a fairly 

 good reticulate stab growth was produced, but no more than in agar 

 stab cultures which were not sealed with vaseline. 



Another experiment was made with the use of cover glasses. In 

 this experiment 10 c. c. of sterile agar were poured into ordinary 

 petri dishes and the soUdified agar inoculated at one point. Sterile 

 cover glasses were then placed over the point of inoculation and 

 pressed down firmly to exclude the air. In 24 hours the growth 

 under the cover glass was distinct and in 48 hours it had reached the 

 edge of the cover glass and eventually spread over the plate. 



No more exhaustive experiments have been carried out. It is 

 beheved that sufficient has been done to show that the organism wOl 

 grow well in a reduced amount of oxygen and will grow moderately 

 well in a very small amount of it. It has not been proved that the 

 organism will grow when there is absolutely no oxygen present. 



LIQUEFACTION OP GELATIN. 



The six coconut cultures were inoculated into beef gelatin and 

 placed ui the gelatin box at about 19° C. All remained perfectly firm, 

 until after 11 weeks when No. 1 was somewhat softened. A few days 

 afterwards No. 1 appeared entirely Hquefied. Six months after inocu- 

 lation all remained firm with the exception of No. 1, which was 

 liquefied. The growth on the surface of these tubes first became thin 

 and white, with an irregular margin. The growth along the stab 

 was at first slender and bordered by and consisting of numerous 

 tiny spherical masses. Eventually the growth spread tlirough the 

 medium and over the entire surface. 



The foregoing experiment was repeated with the same results. 

 The experunent was again tried and No. 1 liquefied after 16 days, 

 while the others remained solid. 



In the work of Longley and Baton ^ for the identification of Bacillus 

 coli the cultures containing the suspected organism are incubated in 



' LoDRley, F. F., and Baton, W. U. C. Notes on the Determination of B. Coli in Water. Journal ol 

 Infectious Diseases, vol. 4, 1907, pp. 397-416. 



228 



