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Mary Davies Swartz, 



definite volume, and examined in a polariscope. The results of these 

 experiments are shown in the following table. Mixtures of B. Pyo- 

 cyaneus, B. Prodigiosus, B. Proteus vulgaris and B. Pyogenes foetidus 

 are designated A, and mixtures of faecal and soil bacteria, B. 



The action of putrefactive organisms upon the dulse preparation 

 was also studied, according to the method used by Slowtzoff (154) 

 in the case of xylan. One hundred grams of chopped lean beef and 

 10 grams of sodium carbonate were added to 1 liter of water, and 

 the mixture allowed to stand in a warm place for three days. Two 

 hundred and fifty cc. were then removed for a control, and to the 

 remainder 0.5 gram of dulse was added. This solution gave a strong 

 pentosan reaction; the control was pentosan-free. The two solutions 

 were put in a warm place, and tested daily for pentosans. After five 

 days' digestion, the reaction of the dulse solution was very much 

 fainter than at first, but it did not entirely disappear till the twelfth 

 or thirteenth day. Slowtzoff found that xylan disappeared in nine 

 or ten days, but his solution was kept at a temperature of 40° C, 

 while these mixtures remained at a temperature of from 30° to 35° C, 

 a condition less favorable for rapid decomposition. 



Solutions of Irish moss were digested with faecal mixtures in the 

 following manner : Human faeces were rubbed to a mud with water. 

 Ten cc. portions of this material were added to flasks containing 50 cc. 

 of a 1 per cent "moss" solution, and allowed to digest in a warm place 

 for 24 hours. A portion of water inoculated in the same way was 

 used as a control. Small portions of these solutions were then evap- 

 orated nearly to dryness, extracted with alcohol, and tested for reduc- 

 ing sugar. The results were wholly negative. 



That limu manauea is not entirely resistant to the action of putre- 

 fying organisms is shown by the following: A solution was made 



