THE ROOT. 69 



cells as the growth of those behind constantly pushes the 

 apex forward through the soil. 



In seed-plants, the segments of the egg which produce the 



Fig. 84. — Transverse section of a young root grown in soil, showing root-hairs with 

 adherent soil-particles, the cortex, and the stele. Magnified about 20 diam. — After 

 Frank. 



root do not divide so as to form a single apical cell, but a 

 group of initial cells, which retain the power of rapid division 

 and constitute a primary meristem or growing point. In all 

 other respects the development of the root from this group 

 of initials is similar to that already described. 



