CHANGES PRODUCED BY A SAPROPHYTIC ANAEROBE 381 



tions than the one used in this work, since but one culture con- 

 tainer wa-s used and all the samples taken from it. Results could 

 not be exactly duplicated, however, by the use of this apparatus. 

 All our cultures were placed in a vacuum as complete as we 

 could obtain. Great difficulty was experienced in avoiding; leaks, 

 and in obtaining a culture vessel which would withstand steriliza- 

 tion and still be strong enough not to be crushed under the high 

 external pressure. At the time this work was done, special glass- 

 ware could not be purchased on the market and "pure" gum 

 rubber tubing that would hold a vacuum was not obtainable. 

 Numerous samples of so-called pure gum rubber, were secured, 

 but none of them would hold a high vacuum for twenty-four 

 hours, although they were coated with celloidin and various 

 cements recommended for this purpose. We desired enough cul- 

 ture material for several tests and this required a large culture 

 vessel. 



DESCRIPTION OF THE APPARATUS 



The following apparatus (fig. 1) was finally devised and met 

 these difficulties veiy well. 



A quart milk bottle (N) was used as a culture vessel. To this 

 was added from 300 to 500 cc. of the culture medium and the 

 bottle was then autoclaved at 20 pounds pressure for thirty 

 minutes. The asparagus was merely suspended in tap water, 100 

 grams in 300 cc. of water. Fresh whole mixed milk was used. 

 The potato medium was made by adding 100 grams of potato 

 to 300 cc. of water. The potato was carefully selected, washed, 

 peeled and passed through a meat grinder; and the potato pulp 

 was washed in running water for several hours. For the carbo- 

 hydrate fermentation tests a 2 per cent peptone solution was used. 

 Three hundred cubic centimeters of this solution were placed in 

 the bottles and sterilized. The carbohydrates were sterilized in 

 10 per cent solution and added at the time of inoculation. 



As an inoculum, we used 1 cc. of a four day old potato-pep- 

 tone-water culture of the organism grown at 37°C. The four day 

 culture seemed to give the best results. At first smaller amounts 



