84 liEl'OET OF CHEMICAL LABOKATOEY 



states that the bacteria found responsible for gum-fliix in Acacia biiiercata also caused 

 production of gum (of a different kind) when made to infect peach trees. In other 

 instances, also, he found that one species of bacterium could produce gum in the 

 tissues of different species of trees. 



In cases of this kind the differences in the chemical nature of the gums are 

 probably due to the presence of different sugars or other constituents in the sap of 

 the various trees. 



In concluding this report, I wish again to express my thanks to Dr. Balfour 

 and Dr. Beam for suggestions and advice which they liave kindly given me in 

 connection with mv work. 



