GRIFFIN. 



[VOL. I. 



20 



2 



10 



12 



FIG. 2. A male Nautilus pompilius seen from beneath, the mantle being folded back over the 

 posterior portion of the body. i. Tentacles. 2. Eye. 3. Infra-ocular tentacle. 4. M. collaris. 

 5. Shell-muscle. 6. Opening of the rudimentary reproductive organs of the left side. 7. Outer 

 nephridial pore. 8. Mantle. 9. Branchial vein of superior gill. 10. Superior osphradium. u. 

 Inferior gill. 12. Mantle. 13. Inferior osphradium. 14. Inner nephridial pore. 15. Viscero- 

 pericardial pore. 16. Anus. 17. Needham's sac. 18. Penis. 19. Opening of penis. 20. Funnel. 



