200 



a manner with the skippings of the Truncatellidce. Although, strictly 

 speaking, a water mollusk, for which reason it is placed by many au- 

 thors with the Rissoa, the Truncatella is able to subsist for a long time 

 on land. Mr. Lowe relates having preserved specimens taken on the 

 shores of Madeira for five weeks in a dry box, which, on being placed in 

 a glass of sea-water, crawled forth alive. 



Only one species, T. Montagui, has been found in Britain. The re- 

 mainder are from the Mediterranean, West Indies, California, Madeira, 

 and Teneriffe, Philippine Islands, Mauritius, Australia, Pacific Islands, 

 Bio Janeiro, etc. 



1. Adamsi, Pfr. 



2. aurantia, Gould. 



3. Bairdiana, Ad. 



4. Barbadensis, Pfr. 



5. bilabiata, id. 



6. Calif ornica, id. 



7. Caribbasensis, Soto. 



8. Ceylanica, Pfr. 



9. clathrus, Lowe. 



Species. 



10. elongata, Poey. 



11. Guerini, Villa. 



12. lirata, Poey. 



13. Lowei, S/t/'/f. 



14. marginata, Kust. 



15. modesta, Ad. 



16. Montagui, Lowe. 



17. povrecta, Gould. 



18. pulchella, Pfr. 



19. rostrata, Gould. 



20. scalariformis, Reeve. 



21. scalaris, Mich. 



22. striatula, Menke. 



23. subcylindrica, Gray. 



24. teres, Pfr. 



25. truncatula, Bunk. 



26. valida, Pfr. 



27. Vitiana, Gould. 



Figure. 



Truncatella CAUiBBiEENSis. PL 20. Pig. 107. Shell, considerably 

 magnified, showing the peculiarity of the truncated apex. 



Genus 6. GEOMELANIA, Pfeiffer. 



Animal ; similar to Truncatella. 



Shell ; imperforated, turreted, whitish, often gloss?/, densely scidp- 

 turea I with longitudinal ribs; apex truncated; aperture some- 

 what squarely ovate, effused, produced at the base into a 

 tongue-like appendage ; lip mostly thickened and reflected. 



Allied to the Truncatella:, with the apex similarly truncated, and with 

 an animal in no respect differing,* are the Geomelanice, a group of shells 

 almost as numerous in species, of more slender form, in which the 

 aperture is curiously effused at the base into a sort of tongue-like appen- 



* Arthur Adams, Pro. Zool. Soc. 1850, p. 169. 



