ALANIS, WO, 
All shells 1.5 times natural size. 
Figs. 1-10. P. hyalina Brod., from Tahiti. 
Fig. 1. Shortest specimen, Tautira Valley. 
Fig. 2. Broadest shell, Otuna Valley. 
Fig. 3. Longest shell, Paraura Valley. 
Fig. 4. Narrowest shell, Tipaerui Valley. 
Figs. 5, 6. Average shells, Fautaua Valley. 
Fig. 7. Thin type, Haavini Valley. 
Fig. 8. Broken and repaired shell, Papenoo Valley. 
Fig. 9. Average shell, showing obliquity of the lip in profile view. 
Fig. ro. Adolescent, Pirai Valley. 
Figs. 11, 12. P. hyalina Brod., from Moki, Cook Islands. 
Fig. 13. P. hyalina Brod., from Mangaia, Cook Islands. 
Figs. 14-17. P. clara parva Cr., Punaruu Valley. 
Fig. 18. P. clara parva Cr., Maruapoo Valley. 
Figs. 19-21. P. clara parva Cr., Atehi Valley. 
Fig. 22. P. clara parva Cr., Papehue Valley. 
Figs. 23-36. P. clara incrassa Cr., Aoua Valley. 
Fig. 37. P. clara minor Cr., Orofere Valley. 
Figs. 38-40. P. clara minor Cr., Vaitupa Valley. 
Figs. 41-42. P. clara minor Cr., Tiamao Valley. — 
