112 



M O L L U S C A 



Tabular View of the Subdivisions of the Class GASTKOPODA, arranged so as to show their supposed Genetic 



Eblationships. 



Class.— GASTROPODA. 

 {Archisoplewrum. ) 



Sub-class 1. — ISOPLBURA. 



Sub-class 2.— Anisopleura. 

 {ArcTiieuthyneurum. ) 



Branch a. — Strbptoneuea. 

 {Archizygohranchiwm. ) 



Branch b. — Euthyneura. 

 {ArcMc^isthohranchiwYi. ) 



9 Q Q Order 1.— Zygobeanohia. 



Q 



o 





Order 2. — ^Azygobeanohia. 

 {Archiholoohlamydum. ) 



Sect. a. 



Sect. 6. 

 Natamiia. 





Order 1. — Opisthobeanchia. 

 [ArcMpalliatum. ) 



Order 2. — Pulmonata. 

 {Arckibasommatum . ) 



Sect. b. 

 Non-Palliata. 



an 



g- 



& 



I 





g- 

 a' 







r §- I 



a Sr 



5w 

 S 



a 



i 



i 

 a 



Bq ta 



^ t 



Family 11. — Naticidse. 



Genera : Natica, Lam. ; Sigaretus, Lam. ; Neritopsis, Gratel. 

 Family 12. — EntocoTiohidse. 

 The single genus and species Entoconcha mirabilis, discovered by 

 Joh. Mtiller in 1851, parasitic in Synapta digitata. The adult 

 form is not known. 

 Family 13. — Marsenidee. 



Genera : Marsenia, Leach ; OtichidiopSis, Beck. 

 Family 14. — Acmseidae. 

 Genera : Acmssa, Eschsch. ; Lottia, Gr. ; (probably these wiU be 

 found to belong to the Zygobranchia). 

 Family 15. — Oa/puUdas. 



Genera : Gapulus, Montf. ; Galyptrsea, Lam. (fig. 40) ; Trochita, 

 Schum. 

 Family 16. — Littorinides. 



Genera : Littorina (the Periwinkles, fig. 46) ; Modulus, Gray ; 

 Lacuna, Turt. ; Mssoa, Frem. ; Hydrobia, Hartm. ; Assiminia, 

 Leach. 

 Family 17. — Pdludinidse. 



Genera : Paludina (Eiver-Snail) (figs. 7, 21) ; BUhynia, Gray ; 

 Twnalia, Gray. 

 Family 18. — Val/mtidBe. 



Genus : Vcdvata (fig. 45), fresh-water. 

 Family 19. — Ampullaridse. 



Genus : AmpuUaria (can breathe air by means of the walls of 

 the palllal chamber as well as water by the gill ; fresh-waters 

 of tropical Aiherica,' Africa, and East Indies). 



Sub-order 2. — Pneumonochlamyda. 

 Characters. — PaLial chamber a lung-sac _; no ^; mouth on a 

 rostrum, not a retractile proboscis;- terrestrial habit. 



Family 20. — Cyelostomidss. 



Genera: CyclostorKa, Lam.; Oycloplwrus, Montf.; Ferussina, 

 Gratel.; Pupina, Vignard. 

 Family 21. — Selicmidse (radula rhipidoglossate rather than tsenio- 



Genera : Stoastoma, Adams ; Trochatella, Swains. ; Eelidna, 

 Lam.; Proserpina, Guild. 

 Family 22. — AdeulidsB. 

 Genera : AmMla, Hartm. ; Geomelania, Pfr. 



Sub-order 3. — Siphonochlamyda. 

 Characters. — Eeptant Azygobranchia with the margin of the 

 mantle drawn out to form a &ough-like siphon which iiotches the 

 lip of the shell ; shell always spiral ; usually an operculum, homy 

 or lamelliform ; either a rostrum or a retractile proboscis j exclusively 

 marine ; mostly carnivorous. 



* Tsenioglossa (3.1.3). 

 Family 1. — Strombidce. 



Genera : Strombus, L. ; Pteroceras, Lam. ; Rostellaria, Lam. 

 (fig. 43). 

 Family 2. — Aporrhaidse. 



Genus : Aporrhais, Da Costa. 

 Family 3. — Pedicularidie. 



Genus : Pedicularia, Swains. 

 Family 4. — Dolidee. 



Genera : Cassis, Lam. ; Cassidaria, Lam. ; Dolvum, Lam. ; Mcula, 

 Swains. 

 Family 5. — Tritonidee. 



Genera : Tritonium, Cuv. (fig. 42) ; Banella, Lam. 

 Family 6. — Oyprasidas (the Cowries). 



Genera : Cyprasa, L. ; Ovulum, Brug. (fig. 41) ; Erato, Risso. 



*Tmdglossa (1.0.1). 

 Family 7. — Conidse. 

 Genus : Conus, L. 

 Family 8. — Terebridse. 



Genus : Terebra, Adans. 

 Family 9. — Pleurotomidse. 



Genus : Pleurotoma, Lam. 

 Family 10. — Cancellaridm. 

 Gentis : Cancellaria, Lam. 



*Ilachiglossa {1.1.1 or .1.). 

 Family 11. — Muricidse. 



Genera : Murex, L. ; Trophon, Montf. ; Fasus, Brug. ; Pyrula, 

 Lam. (flg. 38) ; Turbinella, Lam. 

 Family 12. — Buccinidas. 



Genera : BiKdnum, L. ; Nassa, Lam. (fig. 5) ; Purpura, Brug. 

 (fig. 47); Concholepas, Lam.; Magilits, Montf. 

 Family 13. — Mitridas. 

 Genus : Mitra, Lam. 



