142 : JUMPING PLANT-LICE. 
FiG.{132b—Pachypsylla c. mamma, Ril.: a, leaf with galls from under side—nat- 
ural size; b, section of gall showing cup-like depression, and insect in cavity; 
c, pupa, enlarged. After Riley. 
Pachypsylla venusta O. S. (The Hackberry Gall Psylia). 
This is one of the hackberry inhabiting species, and is much 
larger than all others, expanding nearly half an inch across the 
expanded wing-covers, which are grayish, marked with brown, 
with a double oblique row of squarish dark brown spots along 
the posterior margin of the wing-covers. The gall produced by 
arresting the flow of sap in the petiole of the hackberry leaf some- 
times reaches the size of a large filbert nut. When ripe in autumn 
it is very hard and coarse. The structure of the gall, and that 
of another one (P. c. mamma Ril.), as well as the gall-maker, are 
shown in Fig. 132. These insects are of no economic import- 
ance. 
Fic. 132c—Adult or P. c.-mamma Ril.—enlarged. After Ent. Commission, Div. ot 
Entomology, Dep. of Agriculture. 
