M [CRO ORGANISMS OF M \ru; SAP 509 



3. Hot Fehling's solution in excess was reduced by a por 

 tion of the distillate, giving characteristic copper precipitate 



4. A saturated cooled solution of acid sodium sulphite 

 treated with a portion of the distillate gave no reaction. 



5. The color of a solution of fuchsin, mixed with just 

 sufficient sodium sulphite almost to decolorize it, was not re- 

 stored by the addition of 5 cc. of the distillate, although in 

 some cases there appeared to be a slight suggestion of return- 

 ing color. 



6. A 10% solution of silver nitrate was treated with an 

 equal quantity of to'-' solution of potassium hydroxid ami am- 

 monia was added until the precipitate just dissolved. A 1 

 lion of the distillate added to this reagent gave a metallic mirror 

 after standing for half an hour, or within one or two minutes 

 when the tube containing the mixture was gently heated over 

 a flame. 



The indications were that while aldehyde or ketone or 

 both might be present in small quantities, the greater part of 

 the iodoform must have been produced from alcohol. As a 

 further check upon this conclusion 50 cc. of the distillate produc- 

 ing- iodoform were added to an excess of hot Fehling's solution 

 and the containing flask immediately connected with a condenser 

 and distilled. About 20 cc. of the distillate were collected. An 

 examination of the residue in the Fehling's solution showed a 

 reduction of copper. The distillate gave a copious precipita- 

 tion of iodoform, but failed to react with ammoniacal silver 

 nitrate or with decolorized fuchsin. 



Production of proteolytic ensyms. — The slow liquefaction 

 of gelatin in old cultures and the suggestion of partial digestion 

 observed in old milk cultures indicates that this organism pro- 

 duces proteolytic enzyms only when forced to do so and then 

 only in verv small quantities. In order to determine this point 

 fresh centrifuged milk was passed through several thicknes 

 of fine meshed filter paper, and finally freed from the last traces 

 of fat, and at the same time rendered sterile, by passing it 



