104 



Familki : Cydostomacca. 



1. Apcrostonia Troschol. 



Opcrculuin testaceiiin, arclisp^lnun, cxlu.s concavius- 

 culum. Testa siibturhinato-depressa vel discoidoa. Peri- 

 stoma continuum vel marginilnis callo junctis, rectum vel 

 expansum. 



§• 1« 13. semistriadiDi Sow. 



*14. siiturale Sow. 

 15. plebejuüj Sow. 



§• 2. 

 Peristomate ex{)auso. 



* 16. (iislomella Sow. 

 tJ7. hebraicum (Valvata) 

 Less. 

 18. planorbulumLain.(Cor- 

 nu vehatoriuni Cliem. ?) 

 ••= 19. discoideiim Sow. 



20. mucronatum Sow. 



21. substriatum Sow. 



22. pusilluin Sow. 

 *23. exigiium Sow. 



Peristomate subrecto. 



1. giganteum Sow. 



2. cingulatum Sow. 



3. jamaicense Chemn. 



4. corrugatum Sow. 



5. transliieiduni Sow. 



6. PopayanijmLe;i.(incon- 

 spicuum Sow.?) 



*7. aspcridiim Sow. 

 8. Inca Orb. (Blanclietia- 

 num Moric.) 

 fO. DuCfianum Adams. 

 *10. mexicanum Menke. 



11. stramineiim Reeve. 



12. brasiliense Sow. (pro- 

 minuliim Fer. ?) 



II. Cyclo Stoma Lam. emend. 



Operculum testaceum, paucisj)irum , aaCraclu ultimo 

 lato, nucleo exceutrico. Testa globoso-coiiioa, turbinata 

 ■vel turrita. Peristoma simplex vel duplicatum, continuum 

 vel subinterruptum, rectum vel expansum. 



A. Perist. recto. 



§. 1. 

 Globosa-cüiüia. 

 1. naticoidcs Kecl. (Colia. 

 ccum Chemn.?) 

 t2. candidum Sow. 



*3. albicans Sow. 



4. clatbratulum Kecl. 



5. haemastomum Ant. 

 *6. iiolitum Sow. 



(-7. sjjurcum (»rat. 

 *8. lio-atum Lm. 



