Nov. 19, 1917 
Reactions of Phosphorus of Root of Turnip 
361 
phorus in the plant was 100 to 17 when the minimum amount of phos¬ 
phorus was supplied and about 100 to 300 when there was a liberal 
amount. On account of the indications that possibly an increased per¬ 
centage of phosphorus in the turnip root may be due in a considerable 
degree to an accumulation of inorganic phosphorus, attention was turned 
principally to the aqueous extractive portion rather than to the lipoid and 
residual portions, which constitute only minor parts of the phosphorus 
of the turnip roots. 
It is shown by the following work that a more complete aqueous extrac¬ 
tion of phosphorus can be made of the fresh pulp than of the dried turnip: 
300-gm. lots from the same turnips were in two cases dried in slices at 
about 6o° C., finely ground, and then digested for 36 hours, one with 
800 gm. of distilled water and the other with 0.2 per cent hydrochloric 
acid; and in another case the undried pulp was digested similarly for 36 
hours with about 475 gm. of distilled water, which with that in the tur¬ 
nips equaled the amount used to extract the dried turnips. The amount 
of extracted phosphorus pentoxid, in grams per 100 of dry turnip, was, 
with water, 0.561 from the fresh pulp and 0.500 from the dried material; 
whereas it was only 0.414 when the hydrochloric acid was used as a solvent 
with the dried material. 
To avoid the changes which apparently take place during the drying 
of turnips, attention was next turned to a study of fresh turnips, including 
some of the transformations which occur in connection with the living 
cells. 
MICROCHEMICAL EXAMINATIONS 
A number of similar turnips which had been grown in soil in the green¬ 
house until the thickened roots were 1 to 2 inches in diameter were trans¬ 
ferred to a nutrient solution in bottles. After the turnips had become 
adjusted to the new conditions some of them were deprived of phos¬ 
phorus in the nutrient solution. Six days later it was found upon exami¬ 
nation of one of these for phosphorus with a modified magnesium mixture 
containing only a small amount of ammonium hydroxid that practically 
no crystals of ammonium magnesium phosphate existed in microscopic 
sections, whereas similar turnips from which the phosphorus had not been 
withheld contained an abundance of them. An examination of the cul¬ 
ture solution to which no phosphorus had been added showed that the 
phosphorus originally precipitable by the magnesium mixture had not 
passed out into the solution; therefore it probably had been used in the 
nutrition of the plant. 
Some of the turnips which had been deprived of phosphorus were next 
supplied with liberal amounts in the nutrient solution, so that from time 
to time one of them might be examined for evidences of phosphorus 
absorption. Within 24 hours after phosphorus had been added in the 
nutrient solution crystals of ammonium magnesium phosphate were 
