CYCLOSTOMACEA.. 305 



Sub-Genus LEONIA, Gray. 



22. Cyclostoma (Leonia) mammillaris, Lam. 



4 Oran ; coll. M. Malherbe, ex c. As. Soc., Bengal. 



Sub-Genus TROPIDOPHORA, Troschel. 



23. Cyclostoma (Tropidophora) cuvierianum, Petit. 



2 Nossi-be", Madagascar ; ex c. Evenor Dupont, Esq., and A. Morelet, Esq. 



24. Cyclostoma (Tropidophora) articulatum, Gray. 



6 Kodriguez ; ex c. J. Caldwell, Esq., and Evenor Dupont, Esq. 

 1 Rodriguez (fossil) ; ex c. Evenor Dupont, Esq. 



25. Cyclostoma (Tropidophora) pulchrum, Gray. 



30 Mahe, Praslin, and Silhouette, Seychelles I. ; coll. G. Nevill, Esq. 



26. Cyclostoma (Tropidophora) campanulatum, 



Pfeiffer. 

 1 Madagascar ; ex c. Evenor Dupont, Esq. 



27. Cyclostoma (Tropidophora) occlusum, Morch. 



1 Madagascar; ex c. Evenor Dupont, Esq. 



28. Cyclostoma (Tropidophora) scabrum, H. Ad. 



5 (type) Pouce Mt., Mauritius, under large boulders (semi-fossil) ; coll. 



G. Nevill, Esq. 



29. Cyclostoma (Tropidophora) mauritianum, 



H. Ad. 

 9 Pouce Mt. (with the preceding) ; coll. G. Nevill, Esq. 



30. Cyclostoma (Tropidophora) tricarinatum, 



Mailer. 



2 Mauritius (semi-fossil) ; coll. Eveuor Dupont, Esq. 



1 Mahebourg, Mauritius (semi-fossil) ; coll. G. Nevill, Esq. 



31. Cyclostoma (Tropidophora) caldwellianum, 



n. sp. 



Very close to the preceding ; spire more elevated ; umbilicus 

 less open ; the keels within the umbilicus of greater inequality, 

 one in especial being very prominent. 



Long. 31 ; diam. 30 mil. 



6 Pouce Mt. (type), semi-fossil, together with C. scabrum, C. 



tianum, &c. ; coll. G. Nevill, Esq. 



