A NOTE ON THE ADAPTABILITY OF THE FOLIN 
MICRO-KJELDAHL APPARATUS FOR 
PLANT WORK 
AVIS 
Formerly Research Assistant to the Missouri Botanical Garden 
There is frequent need in most botanical laboratories for 
the determination of small amounts of nitrogen. Recourse is 
usually had to the familiar Kjeldahl method—a method, 
however, which proves rather cumbersome for certain types 
of work. 
Within recent years Folin and Farmer! of the Harvard 
Medical School have modified the original Kjeldahl method 
to the end of determining small amounts of urea nitrogen. In 
their investigations they found the method approached the 
original in accuracy, while in economy of material to be 
analyzed, in reagents, and in time for determination, it was 
superior. 
The Folin modification has been given an extended trial in 
this laboratory, and with a few modifications has been found 
admirably adapted to many phases of plant work. It is espe- 
cially good for demonstration of proteolytic changes, since 
the determination of nitrogen in the different protein frac- 
tions can be readily made. The nitrogen content of minute 
plant sections or organs can be determined—as well as the 
effect of light, darkness, nutrition, disease, etc., upon the 
nitrogen content of various plant parts. The Е 18 also 
adapted for work with advanced classes in plant physiology, 
the apparatus being easily set up, and requiring but little 
desk space and no hood; at the same time it is inexpensive 
to install. 
Apparatus.—The essential parts of the apparatus are as 
follows: 
1. Kjeldahl flasks of 100 or 200 ce. capacity; 
2. Folin fume absorbers ;? 
1 Folin, O., and Farmer, C. J. A new method for the determination of total 
nitrogen in urine. Jour. Biol. Chem. 11: 493-501. 1912. 
2 These can be obtained at most laboratory supply houses. 
ANN. Mo. Bor. GARD., VOL. 3, 1916 (407) 
