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Lizards are much more numerous, and there are several peculiar and interesting forms. Three families are represented; Teidae by two genera—Callopistes peculiar to Chili, and Ameiva which ranges over almost the whole American continent and is found in Patagonia; Geckotidae by four genera, two of which,— Caudiverbera and Homonota—are peculiar to Chili, while Spkcerodaciylus and CvMna are Neotropical, the former ranging to Patagonia, the latter to Chili; and lastly the American family Iguanidae represented by eight genera, no less than six being peculiar, (or almost so,) to the South temperate region. These are Leiodera, Diplolcemus and Proctrotretus, ranging from Chili to Patagonia; Leiohemus, from Peru to Patagonia; Phrymaturus, confined to Chili, and Ptygoderus peculiar, to Patagonia and Tierra del Fuego. The other two genera, Opiums and Lewsaurus, are common to Chili and tropical South America.

Tortoises appear to be scarce, a species of Hydromedusa only being recorded. Of the Amphibia, batrachia (frogs and toads) alone are represented, and appear to be tolerably abundant, seventeen species having been collected by Mr. Darwin in this sub-region. Species of the South American genera Phryniscus, Hylaplesia, Telmatobius, Cacotus, Hylodes, Cyclorhamphits, Pleurodynia, Cystignathus, and Leinperus, are found in various localities, some extending even to the Straits of Magellan,—the extreme southern limit of both Eeptilia and Amphibia, except one lizard (Ptygoderus) found by Professor Cunningham in Tierra del Fuego. There are also four peculiar genera, Rhinoderma belonging to the Engystomidce; Alsodes and Nannophryne to the Bombinatoridse; Opisthodelphys to the Hylidse; and Calyptocephalus to the Discoglossidse.

It thus appears, that in the Keptiles all the groups are typically American, and that most of the peculiar genera belong to families which are exclusively American. The Amphibia, on the other hand, present some interesting external relations, but these are as much with Australia as with the North temperate regions. The Bombinatoridae are indeed Palaearctic, but a larger proportion are Neotropical, and one genus inhabits New Zealand. The Chilian genus Calyptocephalus is allied to Australian tropical genera. The Neotropical genera of Ranidae, five of which extend to Chili and Patagonia, belong to a division which is Australian and Neotropical, and which has species in the Oriental and Ethiopian regions.

Fresh-water Fishes.—These present some peculiar forms, and some very interesting phenomena of distribution. The genus Percilia has been found only in the Rio de Maypu in Chili; and Percichthys, also belonging to the perch family, has five species confined to the fresh waters of South Temperate America, and one far away in Java. Nematogenys (1 sp.) is peculiar to Chili; Trichoinycterus reaches 15,000 feet elevation in the Andes,—both belonging to the Siluridae; Chirodon (2 sp.), belonging to the Characinidae, is peculiar to Chili; and several other genera of the same family extend into this sub-region from Brazil The family Haplochitonidae has a remarkable distribution; one of its genera, Haplochiton (2 sp.), inhabiting Tierra del Fuego and the Falkland Islands, while the other, Prototroctes, is found only in South Australia and New Zealand. Still more remarkable is Oalaxias (forming the family Galaxidse), the species of which are divided between Temperate South America, and Australia, Tasmania, and New Zealand; and there is even one species (Galaxias atlenuatus) which is found in the Chatham Islands, New Zealand, and Tasmania, as well as in the Falkland Islands and Patagonia. Fitzroya (1 sp.) is found only at Montevideo; Orestias (6 sp.) is peculiar to Lake Titicaca in the high Andes of Bolivia; Jenynsid (1 sp.) in the Rio de la Plata —all belonging to the characteristic South American family of the Cyprinodontidae.

Insects.—It is in insects more than in any other class of animals, that we find clear indications of a not very remote migration of northern forms, along the great mountain range to South Temperate America, where they have established themselves as a prominent feature in the entomology of the country. The several orders and families, however, differ greatly in this respect; and there are some groups which are only represented by modifications of tropical forms, as we have seen to be almost entirely the case in birds and reptiles.

Lepidoptera.—The butterflies of the South Temperate Subregion 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: Satyridae, with 11 genera and 27 species, are the most abundant; Nymphalidaa, 2 genera and 8 species; Lemoniidae, 1 genus, 1 species; Lycaenidae, 3 genera, 8 species; Pieridae, 6 genera, 14 species; Papilionidae, 2 genera, 8 species; Hesperidae, 4 genera, 13 species. One genus of Satyridae {Elina) and 2 of Pieridae (Eroessa and Phulia) are peculiar to Chili. The following are the genera whose derivation must be traced to the north temperate zone:— Tetraphiybia, 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 AVneis, a northern genus; Hipparchia, a northern genus yet having a species in Brazil;—all Satyridae. The Nymphalidae are represented by the typical north temperate genus Argynnvs, with 7 species in Chili; Colias, among the Pieridae, 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 (Satyridae); Apodemia (Lemoniidae) confined to Tropical America and Chili. Hesperocharis and Callidryas (Pieridae), both tropical; and Thracides (Hesperidae) confined to Tropical America and Chili. Other genera are widely scattered; as, Epinepkiie 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 HeteropUrw, scattered in Chili, North America, and Tropical Africa. We find then, among butterflies, a large north-temperate element, 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.

Coknptera.—It is among the beetles of South Temperate America that we find some of the most curious examples of remote affinities, and traces of ancient migrations. The Carabidse are very well represented, and having been more extensively collected than most other families, offer us perhaps the most complete materials. Including the Cicindelida?, about 50 genera are known from the South Temperate Sub-region, the greater part from Chili, but a good number also from Patagonia and the Straits of Magellan. Of these more than 30 are peculiar, and most of them are so isolated that it is impossible to determine with precision their nearest allies.

The only remarkable form of Cicindelidse is Agrius, a genus allied to the Amblycheila and Omus of N.W. America. Two genera of Carabidae, Cascellius and Baripus, are closely allied to Promecoderus, an Australian genus; and another, Lecanomerus, has one species in Chili and the other in Australia Five or six of the peculiar genera are undoubtedly allied to characteristic Palsearctic forms; and such northern genera as Carabus, Pristonychus, Anchomenus, Pterostichus, Percus, Bradycellvs, Trechus, and Bembidium, all absent from Tropical America, give great support to the view that there is a close relation between the insects of the northern regions and South Temperate America. A decided tropical element is, however, present. Tropopterus is near Colpodes, a Tropical and South American genus; Mimodromius and Plagiotelium are near Calleida, a South American genus; while Pachyteles, Perieompsus, Variopalpus, and Calleida are widely spread American groups. The preponderance of northern forms seems, however, to be undoubted.

Six Carabidae are known from Juan Fernandez, 3 being identical with Chilian species and 3 peculiar. As the island is 350 miles from the mainland, we have here a proof of how readily insects may be transported great distances.

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