406 M. R. SMIRNOW 



The medium base was made up in moderate quantities, steril- 

 ized in the autoclave and kept until needed. The sugars were 

 added to separate small quantities as required, tubed and steril- 

 ized by the intermittent method. Inoculations were made 

 every fourth or fifth day over a period of fifteen weeks, making 

 a total of twenty-six transfers. Tests were made from the last 

 culture tube to determine biological variations by planting into 

 the various laboratory media, final observations being noted 

 after seven days inoculation. 



This series of experiments was not as successful as the writer 

 desired. Many of the strains suddenly refused to grow, and 

 were lost at different stages of the experiment. This can be 

 explained as due either to a lack of proper nutrition, or, possibly, 

 to an inhibitory action of the sugars, or both. "Sudden death" 

 was also noted by Peckham (1897) in her experiments with 

 B. coll grown in glucose peptone, and is accounted for by her 

 as due to the accumulation of by-products coupled with the 

 complete exhaustion of the bacteria. She believes that on ac- 

 count of incomplete proteolytic activities, through the prefer- 

 ence for the carbohydrate food, there is a deficiency in plastic 

 material of the bacteria sufficient to interfere with reproduction 

 and building up of the cells. Besides the loss of a number of 

 strains, several were found to be contaminated and had to be 

 discarded. 



Though but five cultures were subjected to the carbohydrate 

 action, and two controls were carried through to the completion 

 of the experiment, the writer beheves the results worthy of 

 record, particularly since they verify the results obtained in 

 the work above reported. This is also desirable since the in- 

 tent of these experiments was to show the ability of the controls 

 to retain their various biological characteristics even though 

 subjected to carbohydrates.^ 



Table XII indicates the results obtained. Strains 3 and 6, 

 subjected to the action of glucose in a proteid-free medium, 

 seem to compare well with the results obtained with glucose 



2 These experiments are being repeated, and will again be reported on at a 

 later date. 



