Nov. i8, igrs Physiological Studies of Normal and Blighted Spinach 375 



Wolff (49) reports spinach to have an average iron content of 0.552 

 per cent, calculated on the dry weight of the plant material, and with 

 even this small quantity it is much richer in this element than the vast 

 majority of plants that had then been studied. 



It is interesting to note that healthy spinach tops were here found to 

 contain an average of 0.132 per cent of iron, calculated on the dry weight, 

 against 0.095 per Cent in the blighted tops, in either case a quantity 

 much larger than that recorded by WolfiF. The roots of the diseased 

 plants were found to contain an average of 0.122 per cent of iron and the 

 roots of the normal plants 0.065 per cent. It seems as though a part of 

 the iron that entered the plant through the roots accumulated there 

 instead of going up to the leaves, as in the normal plants. It is interest- 

 ing to note also that when calculated as percentage of the total ash the 

 iron content of the roots always exceeds that of the corresponding tops, 

 a relation more in evidence in diseased than in healthy roots. 



