Kxi'LANATION OF PLATE V. 



FIG. 7. Haliotis cracherodii. Dorsal view. I, 2, pleuro-visceral commissure ; 3, 



4, nerves to the visceral ganglia ; 5> nerves to floor of pallial cavity and efferent gill 

 sinus ; 6, nerve to rectum ; 7, 8, nerves to base of auricles ; 9, nerve to dorsal peri- 

 cardium ; 10, nerve to ventral wall of paricardium and aorta. 



FIG. 8. Lucapina crenulata. Dorsal view. 2, nerve to afferent gill sinus ; 3, 4, 



5, nerves to the wall of paricardial cavity ; 6, nerve to rectum ; 7, nerves to renal 

 organs ; 8, nerve to mantle fissure ; 9, nerve to efferent gill sinus ; 10, nerve to 

 osphradium and gill. 



FIG. 9. Natica levvissii. Dorsal view. I, nerve to dorsum ; 2, nerve to floor of 

 pallial cavity ; 3, nerve to osphradium ; 4, nerve to gill ; 5^ commissure between 

 branchial and left visceral ganglia ; 6, nerve to pericardium, heart and kidney ; 7, 

 ganglia on commissure ; 8, genital nerve ; 9, nerve to paricardium, heart and kidney. 



FIG. 10. Sycotypus canaliculatus. Dorsal view. I, nerve to floor of pallial 

 cavity ; 2, nerve to pericardium and auricle ; 3, nerve to ventricular ganglion ; 4, 

 nerve to liver and genital organs ; 5> nerve to ventricular ganglion ; 7, renal nerve ; 

 8, ganglion on ventriculo-aortic junction ; 9, ventricular nerves ; 10, pleuro-branchial 

 commissure ; II, nerve to hind-gut. 



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