286 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[VoL 11 
CHART III 
PERCENTAGE OP INFECTION 
Here the infestation had been almost eradicated without the aid of 
any predaceous insect enemies. Charts II and III show the amount 
of infestation and percentage of infection in the grove and in tent 2. 
Other Hosts 
Clinging to the under side of the walnut leaves was often found a 
small bark louse belonging to the genus Psocus. These bark lice 
