EXPERIMENT STATION BULLETINS. 539 



may pass through unchanged. At present, however, no one can say how far 

 reaching associative action is or to what practical end it makes its way, but this 

 much is clear: It emphasizes the necessity for pure milk, as to its freedom from 

 bacteria, and as to its proper management. 



I wish to add in closing that experiments are now under way to extend this 

 work in its practical bearing and if possible to secure a more intimate knowledge 

 of its nature. 



I feel grateful to Prof. H. W. Conn for reviewing the manuscript of this article. 



