8 INTRODUCTION TO BOTANY 
of corn, wheat, and oats, in the vegetables and fruits, and 
in the oil of corn and cotton. It must also be noted that 
many tissues or fibers of great significance — such as cotton, 
Fic. 4. A red-oak tree whose roots have lost their anchorage through 
removal of the soil by water 
Compare the position of the tree with that of the beech and other trees 
in the background 
hemp, flax, and the timbers of commerce — are produced in 
connection with the ordinary processes by means of which 
plants manufacture plant foods and use them in their growth. 
