HADIAL NCKve 



NERVE RIN6 



F!C. 142 ECHINODCRMATA 



*hlTEfHOf> 

 CANCLION 



POSTEPIOn 

 GANGLION 



FIG. 143. MOLLUSCA 



B/)AIN 



SUB-PHARYNGEAL GANGLIA 

 FIG. 144 ANNELIDA 



SEGMENTAL 

 GANGLIA 



BRAIN 



EYE 



^UB-OESOPHA GEAL 

 GANGLIA 



SEGMENTAL GANGLIA 



FIG. 14 S. ARTHROPODA 



Figs. 142, 143, 144, and 145. — Some types of invertebrate nervous systems. Diagram- 

 matic. Note the similarity between the systems of the annelid and the arthropod. 



