1912] SKINNER— PHOSPHATE AND CUMARIN 249 



monosodium phosphate, and the disodium phosphate. The 

 reaction of these various phosphates, and probably also the presence 

 of the calcium, appears to modify this action, as indicated by the 

 different figures, but it in nowise determines the effect itself. 

 The conclusion seems warranted that the peculiar action of these 

 phosphate salts in overcoming the toxic action of cumarin is due 

 to the phosphate radical and not to the presence of any particular 

 base, or the acid or alkaline reaction of the nutrient solution. 



Laboratory of Fertility Investigations 



Bureau of Soils 

 Washington, D.C. 



* 





