230 



BACTERIAL ORIGIN OF GUMS OF ARABIN GROUP, 



A similar experiment, in which some of the stages were des- 

 troyed, corroborated these results. It is seen that the bacterium 



0-5 ' 2i 3 4 S %o 



Fig. 2 — The Influence op Asparagine. 



responds quickly to the asparagine, and that the quantity sug- 

 gested by the qualitative test, viz., 0-1%, is an optimum percentage. 

 The 2^^ohihitive actioyi of dextrose ujyon levulose. — In a pre- 

 liminary experiment made with the object of testing the action 

 of asparagine against peptone with various sugars, it was noted 

 that the plates containing invert sugar produced no slime. The 

 experiment is duplicated elsewhere and need not be given, but 

 the curious behaviour of the sugar warranted investigation. 

 The following experiment was made : — 



The Influence of Dextrose in Checking Slime-Formation. 



Grams of Slime in 3 daj'S 

 from lOOc.c. of medium.* 



No sugar ... 

 Dextrose 1% 



2 

 Levulose 1 

 „ 2 

 Invert sugar 1% .. 

 „ 2 . 

 Levulose 1% + dextrose 1% 



W W 2% 





 2 

 2 

 10 

 14 

 2 

 1 

 3 

 3 

 3 



* Asparagine O'l, potassium citrate 0-6, tannin 0-3, agar 2, water 100. 



