_Land Shells._--The Neotropical region is probably the richest on the globe in Terrestrial Mollusca, but this is owing, not to any extreme productiveness of the equatorial parts of the continent, where almost all other forms of life are so largely developed, but to the altogether exceptional riches of the West India Islands. The most recent estimates show that the Antilles contain more species of land shells than all the rest of the region, and almost exactly as many as all continental America, north and south. Mr. Thomas Bland, who has long studied American land shells, points out a remarkable difference in the distribution of the Operculated and Inoperculated groups, the former being predominant on the islands, the latter on the continent. The Antilles possess over 600 species of Operculata, to about 150 on the whole American continent, the genera being as 22 to 14. Of Inoperculata the Antilles have 740, the Continent 1,250, the genera being 18 and 22. The proportions of the two groups in each country are, therefore: West India Islands. American Continent. Operculata Gen. 22 Sp. 608 14 151 Inoperculata " 18 " 737 22 1251 The extensive family of the Helicidæ is represented by 22 genera, of which 6 are peculiar. _Spiraxis_ is confined to Central America and the Antilles; _Stenopus_ and _Sagda_ are Antillean only; _Orthalicus_, _Macroceramus_, and _Bulimulus_ have a wider range, the last two extending into the southern United {20}States. Important and characteristic genera are, _Glandina_, in all the tropical parts of the region; _Cylindrella_, in Central America and the Antilles; _Bulimus_, containing many large and handsome species in South America; _Stenogyra_, widely spread in the tropics; and _Streptaxis_, in Tropical South America. Among the Operculata, the Aciculidæ are mostly Antillean, two genera being peculiar there, and one, _Truncatella_, of wide distribution, but most abundant in the West Indian Islands. The Cyclostomidæ are represented by 15 genera, 9 being peculiar to the region, and 5 of these (belonging to the sub-family Licinidæ) to the Antilles only. Of these peculiar genera _Cistula_ and _Chondropoma_ are the most important, ranging over all the tropical parts of the region. Other important genera are _Cyclotus_ and _Megalomastoma_; while _Cyclophorus_ also occurs all over the region. The Helicinidæ are mostly Neotropical, six out of the seven genera being found here, and four are peculiar. _Stoastoma_, is one of the largest genera; and, with _Trochatella_ and _Alcadia_, is confined to the Antilles, while the wide-spread _Helicina_ is most abundant there. The Limacidæ, or Old World slugs, are absent from the region, their place being taken by the allied family, Oncidiadæ.