{43}_Lepidoptera._--The butterflies of the South Temperate Sub-region are not numerous, only about 29 genera and 80 species being recorded. Most of these are from Chili, which is sufficiently accounted for by the general absence of wood on the east side of the Andes from Buenos Ayres to South Patagonia. The families represented are as follows: Satyridæ, with 11 genera and 27 species, are the most abundant; Nymphalidæ, 2 genera and 8 species; Lemoniidæ, 1 genus, 1 species; Lycænidæ, 3 genera, 8 species; Pieridæ, 6 genera, 14 species; Papilionidæ, 2 genera, 8 species; Hesperidæ, 4 genera, 13 species. One genus of Satyridæ (_Elina_) and 2 of Pieridæ (_Eroessa_ and _Phulia_) are peculiar to Chili. The following are the genera whose derivation must be traced to the north temperate zone:--_Tetraphlybia_, _Neosatyrus_, and 3 allied genera of 1 species each, were formerly included under _Erebia_, a northern and arctic form, yet having a few species in South Africa; _Argyrophorus_, allied to _Æneis_, a northern genus; _Hipparchia_, a northern genus yet having a species in Brazil;--all Satyridæ. The Nymphalidæ are represented by the typical north temperate genus _Argynnis_, with 7 species in Chili; _Colias_, among the Pieridæ, is usually considered to be a northern genus, but it possesses representatives in South Africa, the Sandwich Islands, Malabar, New Grenada, and Peru, as well as Chili, and must rather be classed as cosmopolitan. These form a sufficiently remarkable group of northern forms, but they are accompanied by others of a wholly Neotropical origin. Such are _Stibomorpha_ with 6 species, ranging through South America to Guatemala, and _Eteona_, common to Chili and Brazil (Satyridæ); _Apodemia_ (Lemoniidæ) confined to Tropical America and Chili. _Hesperocharis_ and _Callidryas_ (Pieridæ), both tropical; and _Thracides_ (Hesperidæ) confined to Tropical America and Chili. Other genera are widely scattered; as, _Epinephile_ found also in Mexico and Australia; _Cupido_, widely spread in the tropics; _Euryades_, found only in La Plata and Paraguay, allied to South American forms of _Papilio_, to the Australian _Eurycus_, and the northern _Parnassius_; and _Heteropterus_, scattered in Chili, North America, and Tropical Africa. We find then, among butterflies, a large north-temperate element, {44}intermingled in nearly equal proportions with forms derived from Tropical America; and the varying degrees of resemblances of the Chilian to the northern species, seems to indicate successive immigrations at remote intervals.