8. U. Jones 301 



natant liquid was then siphoned out, the precipitate collected and 

 washed with absolute alcohol. After careful drying in the incubator at 

 20° it was digested in 100 c.c. of sterile distilled water for three hours. 

 The liquid was then passed through the Berkefeld filter. A clear pale 

 yellow filtrate was again j^roduced and poured into a number of sterile 

 tubes plugged with cotton-wool and protected by rubber caps. The 

 action of the two filtrates upon living turnips was then tried in the 

 following way. Thin sections of turnips were placed in small petri- 

 capsules, into some was poured the filtrate obtained from the pulp, into 

 others the filtrate from the watery digest of the alcohohc precipitate. 

 Other capsules coiatained sections in sterile water. Microscopic examina- 

 tion after 24 hours showed no differences between several preparations 

 mounted and the control sections from the sterile water and examination 

 again after several days showed no change in the appearance of the 

 sections. Twelve tubes of the filtrates from both sources were employed 

 upon the sterile turnip sections without any signs of loosening of the 

 cells. The action of the filtrates upon a 1 per cent, starch solution was 

 then tried, but the blue coloration after adding iodine still remained 

 even after prolonged action. Tf an enzymic jiroduct capable of separating 

 the parenchyma of the turnip was present in the diseased pulp, its power 

 of action seemed to have been destroyed in the filter. A new series of 

 experiments on similar lines was performed using a Muencke bacteria 

 filter. This filtrate was again ineffective in loosening the tissues. The 

 filtrates obtained from the watery digests of the alcohohc precipitates 

 obtained from both bouillon and glucose-bouillon seemed to be quite 

 inert in their action on the tissues. The use of the porcelain filters was 

 then discontinued and the alternative method tried of treating the 

 bacterial products with antiseptics. A solution of chloroform was em- 

 ployed. The culture treated was the turbid filtrate obtained directly 

 from the putrid mass formed from diseased turnip. The coarser portions 

 of the pulp were removed as before by pressing through a cloth and 

 merely filtering the liquid through filter-paper. An equal volume of the 

 chloroform solution was then added to the filtrate and the flask vigorously 

 shaken at frequent intervals. To determine the sterility of the product 

 inoculations into tubes of nutrient gelatine were taken and poured into 

 petri-dishes. At the same time thin sterile sections of turnip were 

 treated with the product. After 24 hours" immersion the tissues had 

 become disintegrated and further the poured plates were sterile. 



