| Diplomphalus | 1 |
| Rhytida | 10 |
| Elaea | 1 |
| Parmacochlea | 1 |
| Helicarion | 7 |
| Nanina | 3 |
| Hyalinia | 10 |
| Thalassia | 4 |
| Charopa | 5 |
| Patula (?) | 4 |
| Macrocyclis (?) | 1 |
| Helicella | 10 |
| Planispira | 8 |
| Hadra | 51 |
| Chloritis | 5 |
| Pedinogyra | 1 |
| Thersites | 1 |
| Papuina | 6 |
| Panda | 2 |
| Helix (inc. sed.) | 6 |
| Bulimus (?) | 1 |
| Stenogyra | 1 |
| Tornatellina | 4 |
| Pupa | 3 |
| Vertigo | 4 |
| Perrieria | 1 |
| Succinea | 3 |
| Vaginula | 1 |
| Janella | 1 |
| Georissa | 1 |
| Pupina | 16 |
| Hedleya | 1 |
| Callia | 1 |
| Diplommatina | 3 |
| Ditropis | 2 |
| Dermatocera | 1 |
| Helicina | 8 |
(c) The Melanesian Province includes those islands on which the remarkable group Placostylus occurs, the metropolis of whose distribution is New Caledonia. These islands are very possibly the remains of what was once a much wider extent of land. A single species of Placostylus occurs both on Lord Howe’s I. and in the North I. of New Zealand, but this fact, while highly interesting as indicating a possible former extension of land in a south-easterly direction, is hardly sufficient to bring these islands within the province as now limited. The Solomon Is., although containing Placostylus as far to the west as Faro I., form, as has been already stated, a transitional district to the Papuan province.
New Caledonia.—The chief features of the Mollusca are the remarkable development of the helicoid carnivorous genera Rhytida (30 sp.) and Diplomphalus (13 sp.), and of Placostylus (45 sp.). There is a stray Papuina, and a peculiar form Pseudopartula, but Helix has almost entirely disappeared. Polynesian influence is represented by Microcystis (3 sp.), the so-called Patula (13 sp., many of which are probably Charopa), Tornatellina (2 sp.), and Helicina (20 sp.). Partula does not reach so far south, but there are two species of Janella. The recurrence of Melanopsis (19 sp.), absent from the whole Oriental region, is curious, and forms another link with New Zealand. The curious sinistral Limnaea (Isidora), common with Australia and New Zealand, is abundant.
Fig. 215.—Placostylus caledonicus Pet., New Caledonia, × ⅔.
The New Hebrides link New Caledonia and the Solomons by their possession of the typical heavy Placostylus (5 sp.) of the former, and the lighter and more elegant Charis (2 sp.) of the latter. There are 4 Papuina, and Partula is abundant (18 sp.), but there is no evidence at present that the carnivorous genera or the Melanopsis and Isidora of New Caledonia occur.
The Fiji Is., by the possession of 14 Placostylus of the Charis section, which is entirely absent from the adjacent Tonga group, form the eastern limit of the province. There appears to be only a single Partula, but the Polynesian element, especially as seen in Navicella (8 sp.), Neritina (20 sp.), Helicina (11 sp.), and Omphalotropis (11 sp.), is very strong. The Microcystis (9 sp.) and Trochomorpha (14 sp.) are also of a Polynesian type.
(2) The Australian Sub-region includes the whole of Australia (with the exception of the Queensland province) and Tasmania, with New Zealand and the off-lying islands. The fauna, from the prevalence of desert, is scanty, especially in genera. Land operculates are almost entirely wanting. Limax is not indigenous, though several species have become naturalised. The bulk of the fresh-water species belong to Isidora, and it is doubtful whether Physa occurs at all. Unio has a few species, and also Vivipara, but neither Anodonta nor Ampullaria occur. There are a few Melania and Neritina.
Tropical South Australia.—The Mollusca are scanty, and occur chiefly in the neighbourhood of the rivers, the soil being arid, with no shelter either of trees or rocks. Fresh-water species predominate, and the rich land fauna of Queensland is totally wanting. There are no land operculates, 6 Hadra, 1 Bulimus (?), 1 Stenogyra.
West Australia.—Owing to the deserts which bound it, the Mollusca are very isolated, only one species being common with N., S., and E. Australia. The chief characteristics are Liparus, a form intermediate between Helix and Bulimus, and, among the Helices, the group Rhagada. There are no slugs, no carnivorous snails, and only three land operculates.