96 ANATOMY OF STEMS, ROOTS, AND LEAVES 



higher or flowering plants than in the lower forms. Some cells 

 have thin walls and contain a great deal of food materials which 

 make them valuable foods for man and other animals. Some 

 are fibrous in character and have thick walls which make them 



Fia. 70. Cross-section of fibro-vascular bundle from -corn stem. 



useful in many industries. We will give a brief discussion of 

 these different types of cells. 



Parenchyma. The cells of pith are large, somewhat vari- 

 able in size, thin-walled, more or less spherical in shape and 

 usually show irregular spaces between them. They are known 

 as parenchyma or soft cells. (Fig. 68.) 



The great majority of the cells of fruits, grains and other 

 edible parts of plants are made up of parenchyma cells. Their 



