CYCLOSTOMACKA. 305 



Sub-Genus LEONIA, Gray. 



22. Cyclostoma (Leonia) mammillaris, Lam. 



4 Oran; coll. M. Malherbe, ex c. As. Soc, Ben^'al. 



Sub-Genus TROPIDOPRORA, Trosclicl. 



23. Cyclostoma (Tropidophora) cuvierianum, Petit. 



2 Nossi-be, Madagascar ; ex c. Evcnor Dupont, Esq., and A. Morclet, Esq. 



24. Cyclostoma (Tropidophora) articulatum, Gray. 



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

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



25. Cyclostoma (Tropidophora) pulchrum, Gray. 



30 Mabe, Praslin, and Silbouette, Seycbelles I. ; coll. G. Nevill, Esq. 



26. Cyclostoma (Tropidophora) campanulatum, 



PfeifEer. 

 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. (witb the preceding) ; coll. G. Nevill, Esq. 



30. Cyclostoma (Tropidophora) tricarinatum, 



Muller. 



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



1 Mabebourg, 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, togetlier witb C. scabrum, C. mauri- 



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



