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THE CHILIAN ANDES, WITH CHARACTERISTIC ANIMALS.

Lizards are much more numerous, and there are several peculiar and interesting forms. Three families are represented; Teide by two genera-Callopistes peculiar to Chili, and Ameiva which ranges over almost the whole American continent and is found in Patagonia; Geckotidæ by four genera, two of which,Caudiverbera and Homonota-are peculiar to Chili, while Sphærodactylus and Cubina are Neotropical, the former ranging to Patagonia, the latter to Chili; and lastly the American family Iguanidæ represented by eight genera, no less than six being peculiar, (or almost so,) to the South temperate region. These are Leiodera, Diplolamus and Proctrotretus, ranging from Chili to Patagonia; Leiolamus, from Peru to Patagonia; Phrymaturus, confined to Chili, and Ptygoderus peculiar, to Patagonia and Tierra del Fuego. The other two genera, Oplurus and Leiosaurus, 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, Cyclorhamphus, Pleurodema, Cystignathus, and Leiuperus, are found in various localities, some extending even to the Straits of Magellan,—the extreme southern limit of both Reptilia and Amphibia, except one lizard (Ptygoderus) found by Professor Cunningham in Tierra del Fuego. There are also four peculiar genera, Rhinoderma belonging to the Engystomida; Alsodes and Nannophryne to the Bombinatoride; Opisthodelphys to the Hylidæ; and Calyptocephalus to the Discoglossidæ.

It thus appears, that in the Reptiles 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 Bombinatoridæ are indeed Palearctic, 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 Ranidæ, 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 ; Trichomycterus reaches 15,000 feet elevation in the Andes, both belonging to the Siluridae; Chirodon (2 sp.), belonging to the Characinidæ, is peculiar to Chili; and several other genera of the same family extend into this sub-region from Brazil. The family Haplochitonidæ 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 Galaxias (forming the family Galaxide), the species of which are divided between Temperate South America, and Australia, Tasmania, and New Zealand; and there is even one species (Galaxias attenuatus) 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 Cyprinodontidæ.

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; Nymphalidæ, 2 genera and 8 species; Lemoniidae, 1 genus, 1 species; Lycanidæ, 3 genera, 8 species; Pieridæ, 6 genera, 14 species; Papilionidæ, 2 genera, 8 species; Hesperidæ, 4 genera, 13 species. One genus of Satyrida (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 Satyrida. 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 (Satyrida); 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, 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,

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