THE EPIDERMIS. 



15 



The cells of the epulenui.s 

 adapted to dry, hot climates 

 are very thick, and the cells 

 of those adapted only to 

 moist air are thin, while the 

 •cells of the same species may 



,.,!.. -, Fici. 15.— Sections of a leaf oii'^esfucaoruiavar. 



vary much ni thickness, Cle- glauca {sheep's fescue); o, from a plant grown 



in the sliade with plenty of moisture; h, from a 

 pendinff on a ojreater or less plant grown in greater heat, with much light 

 I '^ » and httle moisture. 1 xl80.— (E. Hackel). 



■exposure to light, heat, and moisture. 



Fig. 16.— This gives some notion of the appearance of the epidermis of Poa pratensis 

 <June grass); a, cross section of blade; h, seen from the upper side; c, oyer tlie hypo- 

 dermal fibers; ti, rows of stomata; c, bands of cells over parenchyma. 1 xl;i).— (bud- 

 worth). 



