DISCUSSION 285 



feel on the basis of our unpublished observations that we have succeeded 

 or are about to succeed v^here others have failed. The guinea pig trans- 

 fer system does not compare with the ease with which leucocyte extracts 

 transfer sensitivity regularly in the human being. And, secondly, I 

 wonder whether the incorporation of the tissue antigens into the foot 

 pad of the guinea pig in Freund's adjuvant might be more conducive to 

 hypersensitization rather than hyperimmunization. 



