Explanation of PI, I, 



Viburnum arl>oricolum HAYATA. 



Fig. 1. A branch. 



2. A flower. 



3. Corolla, expanded. 



4. 5. 6. Stamens, seen from different sides. 



7. An ovary in vertical section. 



8. Fruits. 



9. 10. 11. Putamens, seen from different sides. 

 12. Cross section of a putamen. 



