_Fresh-water fish._--The same general remarks apply to these as to the reptiles. Only one peculiar genus is noted--_Lebistes_, a form of Cyprinodontidæ from Barbadoes; other genera of the same family being, _Haplochilus_, _Rivulus_, and _Girardinus_, widely spread in the Neotropical region; while _Gambusia_ is confined to Central America, Mexico, and the Antilles. Four other families are represented; Siluridæ by _Chætostomus_, found in Portorico and South America; Chromidæ by the South American _Acara_; Mugillidæ by the Central American _Agonostoma_; and Percidæ by the North American _Centrarchus_, of which a species is recorded from Cuba. _Insects._--The various West Indian islands have not been well explored entomologically; one reason no doubt being, that their comparative poverty renders them little attractive to the professional collector, while the abounding riches of Central and South America lie so near at hand. We can, therefore, hardly tell whether the comparative poverty, or even total absence of some families while others seem fairly represented, is a real phenomenon of distribution, or only dependent on imperfect knowledge. Bearing this in mind, we proceed to give a sketch of what is known of the chief groups of Lepidoptera and Coleoptera. _Lepidoptera._--The Neotropical butterfly-fauna is but poorly represented, the majority of the most remarkable types being entirely wanting; yet there are a few peculiar and very characteristic forms which show great isolation, while the majority of the species are peculiar. Four genera are exclusively or characteristically Antillean,--_Calisto_ belonging to the Satyridæ, with four species, of which one ranges to South Carolina; _Clothilda_ {74}(Nymphalidæ) a fine genus which has 4 Antillean species and 2 in Central America; _Lucinia_ (Nymphalidæ) 2 species, confined to Jamaica and Hayti; and _Kricogonia_ belonging to the Pieridæ, which has 2 West Indian species, while 1 inhabits Mexico and Florida. Genera which show a special relation to Central America are _Euptoieta_, _Eumæus_, and _Nathalis_. Almost all the other genera are South American, the total number recorded in each family as occurring in the West Indian islands, being, 3 of Danaidæ; 1 of Heliconiidæ; 2 of Satyridæ; 18 of Nymphalidæ; 1 of Erycinidæ; 4 of Lycænidæ; 6 of Pieridæ; 1 of Papilionidæ, and 10 of Hesperidæ. The genus _Papilio_ is represented by about 20 species, 2 of which are North American, 4 South American, while the rest form little characteristic groups allied to those of Central America. The most marked feature seems to be the scarcity of Satyridæ and the almost total absence of Erycinidæ, with a great deficiency in characteristic Neotropical forms of Danaidæ and Nymphalidæ.