23y BACTERIAL ORIGIN OF GUMS OF ARABIN GROUP, 



Influence of Temperature. 



Z2-\ 



18 



5 - 



,j, ,4. 170 2.2' 30" 



Fig. 4. — The Influence of Tempekatuke. 



In the first experiment the curve of the numbers showed that 

 the optimum temperature was either about 17° orbelowl4°. The 

 second indicated that the former temperature was the best and 

 that the curve did not fall so rapidly on the lower side of the 

 optimum as it did on the higher. The third experiment corro- 

 borated the second generally. The slime was much more rapidly 

 formed at 22° than at 17°, the bulk being produced in 24 hours. 

 At 17°, the slime was chiefly formed between the second and 

 third day. 



The best artificial medium. — In reviewing the numerous experi- 

 ments, it appears that so long as levulose and asparagine are 



* Asparagine 0*1, levulose 2*0, tannin Q-l, potassium citrate 0-1, agar 2, water 100 grms. 

 Commercial tannin was used in No. 3. 



