Cainozoic Gasteropods are exceedingly abundant in beds of that system in Australasia. The Cainozoic marine fauna in Australia is practically restricted to the States of Victoria, South Australia, and Tasmania; whilst New Zealand has many species in common with Australia.
Genera.—
The commonest genera of the marine Cainozoic or Tertiary deposits are:—Haliotis, Fissurellidea, Emarginula, Subemarginula, Astralium, Liotia, Gibbula, Eulima, Niso, Odostomia, Scala, Solarium, Crepidula, Calyptraea, Natica, Rissoa, Turritella, Siliquaria, Cerithium, Newtoniella, Tylospira, Cypraea, Trivia, Morio, Semicassis, Lotorium, Murex, Typhis, Columbella, Phos, Nassa, Siphonalia, Euthria (Dennantia), Fusus, Columbarium, Fasciolaria, Latirus, Marginella, Mitra, Volutilithes, Voluta, Harpa, Ancilla, Cancellaria, Terebra, Pleurotoma, Drillia, Conus, Bullinella and Vaginella.
Persistent Species.—
Amongst the Cainozoic Gasteropoda of southern Australia which have a persistent range through Balcombian to Kalimnan times, we find:—Niso psila, Crepidula unguiformis (also Werrikooian and Recent), Natica perspectiva, N. hamiltonensis, Turritella murrayana, Cerithium apheles, Cypraea leptorhyncha, Lotorium gibbum, Volutilithes antiscalaris (also in Werrikooian), Marginella propinqua, Ancilla pseudaustralis, Conus ligatus and Bullinella exigua.
Balcombian Gasteropods.—
Species restricted to the Balcombian stage include Scala dolicho, Seguenzia radialis, Dissocheilus eburneus, Trivia erugata, Cypraea ampullacea ([Fig. 102 A]), C. gastroplax, Colubraria leptoskeles, Murex didymus ([Fig. 102 B]), Eburnopsis aulacoessa ([Fig. 102 C]), Fasciolaria concinna, Mitra uniplica, Harpa abbreviata, Ancilla lanceolata, Cancellaria calvulata ([Fig. 102 D]), Buchozia oblongula, Pleurotoma optata, Terebra leptospira and Vaginella eligmostoma ([Fig. 102 E]), (also found at Gellibrand River).
Fig. 102—CAINOZOIC GASTEROPODA.
A—Cypraea ampullacea, Tate. Cainozoic (Balc.) Victoria
B—Murex didymus, Tate. Cainozoic (Balc.) Victoria
C—Eburnopsis aulacoessa, Tate. Cainozoic (Balc.) Victoria
D—Cancellaria calvulata, Tate. Cainozoic (Balc.) Victoria
E—Vaginella eligmostoma, Tate. Cainozoic (Balc.) Victoria