86 THE COCKROACH 



slender pair of connectives (arising from the top of the ganglia) with the first 

 pair of thoracic ganglia Ij^ng in the pro-thorax. There is a pair of ganglia in 

 each of the thoracic segments and in each of the first six abdominal segments. 

 A double ventral nerve-chain connects the ganglia ; each pair supplies its 

 own segment with nerves, while the sixth, abdominal ganglion supplies its own 

 segment and also the posterior segments of the body. 

 Make a drawing of the nervous system. 



