INSECT ENEMIES OF EASTERN FORESTS leg: 
ondary ribs of the leaves of pin oak and round-leaved scrub oak. They 
are about 5 mm. long and are caused by Parallelodiplosis florida Felt. 
The oak pill gall is a globose or subglobose, irregular, reddish, 
wrinkled leaf gall with a diameter of 3 or 4 mm. made on red oak by 
Cincticornia pilulae (Walsh). Undetermined specifically is a leaf 
gall (fig. 136) caused by 7tonzda sp. on chestnut oak. 
RHODODENDRON (RHODODENDRON ) 
The presence of Giardomyia rhododendri Felt may he detected by 
the. swollen, pale-yellowish, inrolled leaf margins which fold over 
the midrib of the. smaller leaves of rhododendron. The affected 
leaves, When expanded, bear indistinct greenish bulges or, in a heavy 
Figure 136.—Gall on leaf of chestnut oak caused by [tonida sp. 
