PLATE XL. 



Fig. 22. Outline of leaf, showing frequency of calcium oxalate crys- 

 tals. X 8. 



Fig. 23. Outline of leaf, showing venation, x 8. 



Fig. 24. Epidermis of leaf, x 182. a, elongated epidermis on top of 

 leaf. 



Fig. 25. Diagramatic drawing of tip of leaf, x 65. a, spine; 6, basi 

 fibers; c. tracheal tube; rf, epidermis; e, palisade parenchyma; /, short 

 chloroplast-bearing parenchyma; g, aqueous tissue; /(. calcium oxalate 

 crystals. 



Fig. 26. Longitudinal section through vein, x 375. 



Fig. 27. Cross section of paligade parenchyma and short chloroplast- 

 bearing cells, x 375. 



Fig. 28. Tangential section of short chloroplast-bearing cells, x 375. 



Fig. 29. Water-storage aqueous tis.sue. «, plastids. 



