ACTION OF BACT. ABORTIVO-EQUINUS ON CARBOHYDRATES 473 



The gas production is recorded as accurately as possible from 

 the action in the inverted vials. Observations were made at 

 twenty-four, forty-eight and seventy-two hour intervals. A 

 comparison of the results in regard to gas production in the 

 heated and unheated media is shown in the preceding table. The 

 results of Meyer and Good, both of whom used heated media, 

 are appended. 



It will be noted that gas was obtained in lactose only from the 

 heated media. Good and Corbett obtained gas in many trials 

 with this sugar but Meyer and Boerner report "no gas." As a 

 result of our work we believe that the gas production in lactose 

 recorded by Good and Corbett is due to the hydrolysis of the 

 carbohydrate by sterilization. The work of Mudge clearly 

 pointed out that discontinuous Arnold sterilization hydrolizes 

 lactose and the results here recorded show that no gas was pro- 

 duced by any of the strains in the unheated lactose media. 



In sucrose bouillon a variation in the results obtained in the 

 heated media is noted. In one trial no gas was produced by any 

 strain, in another only a very small amount. None was found 

 at any time in the unheated sucrose media. Good and Corbett 

 likewise record a smaller number of positive gas productions in 

 this carbohydrate while Meyer and Boerner record "no gas." 



In this work all strains have failed to produce gas in raffinose in 

 both the heated and unheated media while all strains have pro- 

 duced gas in rhamnose. The first trial (rhamnose) however, 

 showed much less gas in the unheated media than the second. 

 The fermentation of rhamnose with gas agrees with the work of 

 Meyer and Boerner but is contrary to the results of Good and 

 Corbett. A small amount of gas was formed by all strains in 

 both heated and unheated inulin broth. In as much as Bad. 

 abortivo-equinus produces large amounts of gas in maltose, the 

 ease with which this sugar is broken down by heat sterilization 

 is not shown. 



The carbohydrates which are fermented with the production 

 of large amounts of gas show a nearly steady increase in acidity 

 during a thirty day period. Dulcitol is an exception to this rule. 

 There seems to be a marked variation in the action of the differ- 

 ent strains of Bad. abortivo-equinus on this carbohydrate. This 



