CHAPTER VI 



THE NERVOUS SYSTEM 



The Nervous System of the Dragonfly (fig. 54) consists of the 

 following principal parts: 



(1) The Brain or Supraoesophageal Ganglion, situated in the 

 head, above the oesophagus. 



(2) The Suboesophageal Ganglion, also situated in the head, 

 but below the oesophagus, and connected with the brain by a pair 

 of circumoesophageal commissures. 



(3) The Ventral Nerve-Cord, running ventrally through the 

 thorax and abdomen, and swollen into paired ganglia at intervals. 



(4) The Sympathetic Nervous System, innervating a portion of 



TABLE OF PARTS or THE CENTRAL NERVOUS SYSTEM. 



Segment 

 HEAD 



1st or Ophthalmic 



2nd or Antennary 

 3rd or Intercalary 



Ganglion 



Parts Innervated 



Remarks 



Protocerebrum Compound Eyes and^l 

 Lateral Ocelli 



Deutocerebrum Antennae and Median I T> 

 f*. n > = . brain 



Ocellus ( 



Tritocerebrum [gives off Sympathetic 



System]J 



{Mandibles 

 1st Maxillae 

 Labium 



Fore legs 



Middle legs, fore-wings 



Hind legs, hind-wings ^ Fused in imago 



Segmental muscles, 

 dorsal vessel, repro- 

 ductive organs (from 

 8th), etc. 



Moves up into 

 seg. 1 in imago 



Innervates segs. 

 8-10 and re- 

 productive or- 



