The Nervous System and the Senses 
163 
mit stimuli from the sense organs and some to carry stimuli 
from the nervous system to the various organs of the body. 
The nerve fibers there¬ 
fore are often compared 
with wires used in con¬ 
ducting electric energy 
from place to place. 
In an hypothetical 
generalized insect em¬ 
bryo we should doubt¬ 
less find a ganglion for 
each segment of the 
body, probably twenty 
in all, but the ganglia 
of the bee larva are 
modified from the primi¬ 
tive condition and in 
the adult still further 
specialization is ob¬ 
served, by the fusion 
of various ganglia. 
The brain (Fig. 85), 
situated above the oesoph¬ 
agus, consists of three 
consecutive ganglia, rec¬ 
ognizable in the embryo, 
but completely fused and 
not readily recognizable 
in the adult. From the 
brain, two short connec¬ 
tives (circum-cesopha- 
geal) pass one on either side of the oesophagus to the 
suboesophageal ganglion ( SceGng ) also located in the 
head. Continuous with the brain are the optic lobes (Opt) 
forming the nervous connection with the large compound 
eyes ( E ), and from the brain are nerves to the antennae 
( AntNv ) and also to the frontal ganglion ( FtGng ), from 
Fig. 84. — Nervous system of worker, 
dorsal view. 
