« LNSECTA. 249 
Fig. 167.—Tue Hive Bree (Apis mellifica). 
Drone ¢. Queen ¢?. Worker or Neuter. 
Three sorts of individuals. 
and the workers, which are sterilised females. In the ants 
the workers have no wings. 
The gall-fly lays its eggs on plants and the “gall” is 
produced by the plant around the egg. The insect, escapes 
from the “gall” by a small hole. The ichneumon-flies 
Fig. 168.—Tur GALL-FLy (Cynips guercus-foliz). 
The galls are shown on the left, the interior of a gall on the right, and the 
: perfect fly below, 
are of economic value from their habit of laying eggs in 
caterpillars of certain Lepidoptera. The larvee feed on the 
substance of the caterpillar and eventually kill it. The 
saw-flies have larvee somewhat like caterpillars but with more 
legs. They are sometimes called “false” caterpillars and 
