THE ROOT-SYSTEM OF IMPATIENS ROYLEI, 509 
2. Injury to roots. 
(a)—In ten roots the tip was removed. 
Result. 
A crown of rootlets was developed just behind the injury. In roots 
showing narrowing towards the tip the ring of rootlets was generally 
given off at the junction of the broad and narrow portions. 
(b) —Several roots had a length of one to two centimetres cut off. 
Result. 
Numerous rootlets developed behind the injury.  Text-figs. 11а & b 
E 
Fig. 17.—a. Rootlets developing from an injured adventitious root growing from the swollen 
base of a lateral branch. №. Side view of the same. с. Adventitious root with 
rootlets arising in two rows as the result of a cut made at right angles to the 
soil (seen from below). d. Side view of an injured root with a cut running 
parallel with the soil. 
Fre. 18.—а. Stunted aerial root with a thick protecting layer of cork. 6. Root from 
lateral branch showing typical narrowing and rootlets arising about the Junction 
of the broad and narrow regions. с. Root showing apparent dichotomy. 
d & e. Roots developing three and four new apices respectively. 
show this feature in front and side view respectively. "The root was growing 
from the swollen base of a lateral branch, and was therefore abortive, but 
the rootlets attained the considerable length of five and a half centi- 
metres. 
LINN. JOURN.—BOTANY, VOL, XLIII, 2P 
