MOLLUSCA 



497 



os,<i. 



Fig. 365, Comparison of gasteropod nervous systems. From Shipley and Mac- 

 Bride. A, Haliotis tiiberculata. B, Limnaea peregra. ce.g. cerebral ganglia; 

 ct. ctenidium; ?na.n. nerve to mantle; os.g. osphradial ganglia; pa.g., ped.g., 

 pl.g. parietal, pedal and pleural ganglia; ped.n. non-ganglionated pedal nerves 

 oi Haliotis connected by commissures; vis.g. visceral ganglia. 



Bi 32 



