PLATE 34 
Longitudinal section of stem of Ricinus communis showing further effects of vapor 
of monobasic ammonium phosphate. Same plant as shown on Plate 32, but in another 
place—that is, in the upper end of the tube internode showing ceiling and side-wall 
tumors, and the lower end of the unopened intemode above bearing a floor tumor, the 
tip of which (X) is normal (see PL 33). Exposure begun on August 21, 1916. 
Photographed on September 2. X5. For a longitudinal section through a normal 
node of Hie same age see Plate 35. 
