PLATE 16 
Fig. A.—Grain bodies of Connecticut Broadleaf tobacco as seen in ordinary trans¬ 
mitted light. a, Idioblasts containing sand crystals of calcium oxalate. X about 300. 
Fig. B.—Representative grain bodies of class 1. X 19.5. 
Fig. C.—Representative grain bodies of class 2. The high lights show the positions 
of the distended epidermal cells. X 19.5. 
Fig. D.—Representative grain bodies of class 3. X 19.5. 
Fig. E.—Representative grain bodies of class 4. X 19.5. 
Fig. F.—Grain substance in the form of minute spherites. Photographed with polar¬ 
ized light. X 280. 
