440 ' Journal of Agricultural Research voI.xii.No. 7 



While it is realized that in most instances these data are insufficient 

 to express results in percentages, and for this reason reference to the 

 percentage of efficacy of a drug has been avoided in the text, it was 

 thought that comprehensive tables like the following would prove 

 convenient in summarizing the results and would at least serve to indi- 

 cate what drugs offer promise of success. Too much emphasis, however, 

 should not be placed on negative results based in most cases on insuffi- 

 cient data. 



The tables do not include some of the earlier experiments carried 

 out on hogs, in which the efficacy of the drug tested was determined 

 solely by the results of fecal examination without killing and examining 

 the animals post-mortem. 



