Glandina 4 Selenites 6 Limax 4 Vitrina 4 Vitrinozonites 1 Mesomphix 15 Hyalinia 22 Conulus 1 Gastrodonta 9 Pristiloma 2 Tebennophorus 4 Ariolimax 6 Prophysaon 2 Hemphillia 1 Binneya 1 Patula 18 Punctum 2 Arionta 20 Praticola 2 Glyptostoma 1 Mesodon 27 Stenotrema 11 Triodopsis 21 Polygyra 23 Polygyrella 2 Gonostoma 1 Vallonia 1 Strobila 2 Pupa 18 Vertigo 8 Holospira 2 Cionella 1 Bulimulus 6 Macroceramus 1 Succinea 21 Vaginulus 1 Helicina 2 =F. The Neotropical Region= The land Mollusca of the Neotropical Region stand in complete contrast to those of the Nearctic. Instead of being scanty, they are exceedingly abundant; instead of being small and obscure, they are among the largest in size, most brilliant in colour, and most singular in shape that are known to exist. At the same time they are, as a whole, isolated in type, and exhibit but little relation with the Mollusca of any other region. The most marked feature is the predominance of the peculiar genera _Bulimus_ and _Bulimulus_, the centre of whose development appears to lie in Peru, Ecuador, and Bolivia, but which diminish, both in numbers and variety of form, in the eastern portion of the region. In the forests of Central America, Venezuela, and Ecuador, and, to a lesser degree, in those of Peru and Brazil, occurs the genus _Orthalicus_, whose tree-climbing habits recall the _Cochlostyla_ of the Philippines. These three groups of bulimoid forms constitute, as far as the mainland is concerned, the preponderating mass of the land Mollusca. _Helix_ proper is most strongly developed in the Greater Antilles, which possess several peculiar groups of great beauty. In Central America _Helix_ is comparatively scarce, but in the northern portions of the continent several fine genera (_Labyrinthus_, _Isomeria_, _Solaropsis_) occur, which disappear altogether towards the south. Carnivorous land Mollusca are, so far as Central America is concerned, more highly developed than in any other quarter of the world, particularly in the genera _Glandina_ and _Streptostyla_. These genera also penetrate the northern portions of the continent, _Glandina_ reaching as far as Ecuador, and _Streptostyla_ as far as Peru. The Greater Antilles have also characteristic forms of these genera. _Streptaxis_ is tolerably abundant all over tropical South America, and is the one pulmonate genus which shows any affinity with the African fauna. The slugs are exceedingly scarce. _Vaginula_ occurs throughout, and is the only genus in any sense characteristic.