PLATE L. 



Gsertneria deltoidea Torr. 



Fig. 35. Tangential section of leaf, showing tracheal elements, and 

 adjacent parenchyma cells. X 575. 



Fig. 36. Composite drawing showing epidermal cells at surface, pali- 

 sade tissue just beneath, and at deepest focus the tracheal elements. 

 X 400. 



Fig. 37. Showing tangential section of tracheal elements and thick- 

 walled water-storage parenchyma tissue. X 550. 



Fig. 38. Surface view of leaf epidermis, x 560. 



