[Vol. 10 



54 



ANNALS OF THE MISSOURI BOTANICAL GARDEN 



tose and maltose, dissolved in the Dunham's solution appeared to 

 have been slightly altered during the process of sterilization in 

 the Arnold sterilizer, but it seems doubtful if the changes which 

 are indicated by the figures are significant even in the case of 



d maltose, since, as has been 



( 



zed to a certain extent by a variability in reducin 



are charac 

 power. 



On the other hand, reference to table ix emphasizes clearly 

 the fact that a considerable hydrolysis of the di- and polysac- 

 charides occurred in the acidulated broths exposed in the auto- 

 clave, and to a lesser extent in those exposed in the steamer. 

 It also appears that sucrose is most markedly affected. Accord- 

 ing to my tests, lactose, maltose, and potato starch in slightly 

 acidulated broth are not hydrolyzed by exposure to moist heat 

 in the process of sterilization at 100° C. 



The data given below are of interest when compared with 

 the quantitative data presented in table ix. These data, fur- 

 thermore, serve as a check on the other type of analysis. 



TABLE VIII 



RESULTS OF COL.ORIMETRIC TEST 



WITH [ODINE. 



Carbohydrate 



Controls 

 Magenta 



Blue 



Autoclave 





Arnold Steamer 



Dextrin 

 Potato starch 



No color 

 Magenta 



Very pale magenta 



Blue 



In the other tables (ix-xiii) are presented data bearing on 

 the quantitative consumption of chosen carbohydrates by a few 

 microorganisms. Nine of the 12 cultures employed were repre- 

 sentative strains of the blackleg bacillus and among the 9 were 

 the 4 "species" of this bacillus, which, together with the other 

 strains, were studied comparatively at an earlier date (see Part 

 II). In addition to these, cultures of Bacillus coll, B. vulgatus, 

 and a species of yeast (probably a species of Saccharomyccs) were 

 investigated. For the sake of facilitating comparisons the 

 amounts of carbohydrate consumed, in terms of glucose, are as- 

 sembled in table xiv. 



discussion 



The data presented in tables ix-xiv call for very little fur 

 ther commentarv. but the action of strain numbers 195 and 19l 



(table xi and 



in the presence of sucrose attract special 



