THE ROOT OF THE ANGIOSPERM 33 
the inside. This structure is called the Root-Cap 
(fig. 18), and serves to protect the delicate growing point 
of the young root from damage as it burrows its way 
through the particles of soil. Some distance behind 
the root-cap the outside layer of the root bears innumer- 
able fine hairs. These hairs are called Roor-Harrs 
(fig. 18) and are chiefly organs of absorption. When 
Ww 
Fic. 18,—Longitudinal Section through Tip of a Young Root 
Showing :— 
W. Root-cap. H. Root-hairs. EE. Piliferous layer. R. Cortex. 
G. Pith. 
one considers that each of the innumerable rootlets of 
a plant bears hundreds of these hairs, it will be under- 
stood how enormously they increase the area of absorp- 
tion of the root system. Also these delicate thread-like 
structures can cling very closely to, and even wrap 
round particles of the soil, thus bringing the root in 
very close contact with the soil. Consequently, if a 
young seedling be pulled ae of the soil it drags up with 
