ILLUSTRATIONS 



FIG. PAGE 



1. Diagram of the Lateral Wall of the Right Nasal Cavity of Man . . 24 



2. Diagram of a Transverse Section of the Right Naaal Cavity of Man 25 



3. Respiratory Epithelium from the Nasal Cavity of a Young Pig 27 



4. Olfactory Cleft of Man 28 



5. Olfactory EpitheUum from a Pig Embryo 29 



6. Olfactory EpitheUum from a Young Mouse 30 



7. Isolated Olfactory Cells and Sustentacular Cells from Man 31 



8. Isolated Olfactory Cell and Sustentacular Cell from a Frog 32 



9. Olfactory Cell of a Pike Showing Flagellum 33 



10. Olfactory Epithelium from a Chick Embryo 36 



11. Ventral View of the Head of a Shark (Scyllium) 38 



12. Diagram of the Right Nasal Cavity of Man Showing the Direction 



of the Inspired Air Currents 46 



13. Simple Rubber Olfactometer 50 



14. Double Olfactometer 51 



15. Ventral View of the Head of a Hammer-head Shark 66 



16. Curves of Olfactory Exhaustion 71 



17. Olfactory Prism 75 



18. Generalized Diagrams of the Molecular Structure of Classes 



of Aromatic Bodies (Olfactory StimuU) 80 



19. Head of Human Embryo showing Vomero-nasal Pore 93 



20. Diagram of the Median Face of the Left Nasal Cavity of Man 94 



21. Transverse Section of the Snout of a Young Frog 95 



22. Transverse Section of the Head of a Snake Embryo 96 



23. Transverse Section of the Nasal Septum of a Young Cat 97 



24. Epithelium from the Vomero-nasal Organ of the Sheep 98 



11 



