CEPHALOPODA 



the visceral hump. The cerebral ganglia are much more differentiated 

 than any of the others. They can be divided into separate regions 

 which co-ordinate the movements of organs for the performance for 

 such complicated actions as feeding, swimming and creeping. In the 



-yten.n. 



Fig- 383. Nervous system of Sepia. After Hillig. bra.g. brachial ganglion; 

 br.g. branchial ganglion and nerve; ce.g. cerebral ganglion; gas.g. gastric 

 ganglion; ma.n. mantle nerve; olf.n. olfactory pit and nerve; op.g. optic 

 ganglion; s.buc.g. superior buccal ganglion; st.g. stellate ganglion; syni.n. 

 sympathetic nerve; ten.n. tentacular nerves; vis.g., vis.n. visceral ganglion 

 and nerve. 



visceral ganglia there are also two sharply defined centres which 

 control the movements of the whole mantle in in-breathing and out- 

 breathing respectively as well as numerous small centres, the stimu- 

 lation of which causes contraction of small muscle patches in the 



