460 
E. H. TOOLE AND W. E. TOTTINGHAM 
was taken out of solution by the higher application of Fe(0H)3, 
presumably by the formation of insoluble ferric phosphate. There was 
no evidence of poor phosphorus nutrition in this case ; on the contrary, 
this was by far the best culture of barley, both in yield and in appear- 
ance. 
7. Treatment with Fe(0H)3 also produced neutrality of the nutrient 
medium, which may have been a factor contributing to the higher 
yield. 
8. Peas, although deprived of a large portion of their cotyledons, 
had not yet developed significant differences in the various culture 
solutions during the growth period of twenty-one days. 
9. With the proportions and kinds of solids and solutions obtaining 
here, there is no clear evidence of adsorption of nutrient ions. 
This work was done in the Department of Agricultural Chemistry 
of the University of Wisconsin. 
Purdue University, 
University of Wisconsin 
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