Observations on the Osazone Method of locating 
Sugars in Plant Tissues. 
BY 
SYDNEY MANGHAM, M.A., 
Lecturer in Botany, Armstrong College , Newcastle-on- Tyne, in the University of Durham. 
With Plate XVII. 
I N the course of a research upon the paths of translocation of sugars in 
plants it has often been necessary to determine the distribution of sugars 
in the tissues after the plants have been subjected to known external con¬ 
ditions. 
The method which has been employed for this purpose is that intro¬ 
duced by Senft , 1 and consists essentially in the production of osazones by 
means of a glycerine solution of phenylhydrazine acetate, a reagent having 
good penetrative powers. 
Descriptions of the method and of some results obtained by it have 
already been published , 2 but more recent investigations have thrown addi¬ 
tional light on the value of the method and on the limits of its application. 
For this reason it is considered desirable to give in the present paper a more 
detailed account of the conclusions arrived at with regard to the use of 
Senft’s reagent and to the interpretation of results yielded by it. In itself 
the paper forms a necessary prelude to the publication of results obtained 
in the above-mentioned research. 
General Method. 
The reagents employed are phenylhydrazine hydrochloride and sodium 
acetate dissolved separately in about ten times their weight of pure 
glycerine . 3 Sodium acetate dissolves fairly readily in warm glycerine. The 
phenylhydrazine hydrochloride should be rubbed up with glycerine in a 
mortar, warmed and well shaken in a bottle kept stoppered to prevent 
1 Senft (’ 04 ). 2 Mangham (* 10 , ’ll). 
3 Commercial glycerine is often adulterated with sugars. 
[Annals of Botany, Vol. XXIX. No. CXV. July, 1915.]’ 
