The most interesting of all the Bolivian animals, however, are the guanaco (_Auchenia huanaco_) and its congeners, the llama (_A. llama_), alpaca (_A. pacos_) and vicuna (_A. vicugna_), belonging to the Camelidae, with the structure and habits of the African camel, but smaller, having no hump, and inhabiting a mountainous and not a level sandy region. They are able to go without food and drink for long periods, and inhabit the arid and semi-arid plateaus of the Andes and the steppes of Patagonia. The guanaco is supposed to be the original type, is the largest of the four, and has the greatest range from Peru to Tierra del Fuego. The llama and alpaca were domesticated long before the discovery of America, but the guanaco and vicuna are found in a wild state only. The llama is used as a pack animal in Bolivia and Peru, and its coarse wool is used in the making of garments for the natives. The alpaca is highly prized for its fine wool, which is a staple export from Bolivia, but the animal is reared with difficulty and the product cannot be largely increased. The vicuna also is celebrated for its wool, which the natives weave into beautiful and costly _ponchos_ (blanket cloaks) and other wearing apparel. The guanaco is hunted for its skin, which, when dressed, makes an attractive rug or robe. The slaughter of the guanaco and vicuna is rapidly diminishing their number. The rearing of llamas and alpacas is a recognized industry in the Bolivian highlands and is wholly in the hands of the Indians, who alone seem to understand the habits and peculiarities of these interesting animals. Of birds and insects the genera and species are very numerous and interesting. The high sierras are frequented by condors and eagles of the largest size, and the whole country by the common vulture, while the American ostrich (_Rhea americanus_) and a species of large stork (the _bata_ or _jaburu_, _Mycteria americana_; maximum height, 8 ft.; spread of wings, 8 ft. 6 in.) inhabit the tropical plains and valleys. Waterfowl are numerous and the forests of the warm valleys are filled with song-birds and birds of beautiful plumage. Many species of humming-birds are found even far up in the mountains, and great numbers of parrots, araras and toucans, beautiful of feather but harsh of voice, enliven the forests of the lowlands. Like other South American states, Bolivia benefited greatly from the introduction of European animals. Horses, cattle, sheep, goats, swine and poultry were introduced, and are now sources of food and wealth to a large part of the population. Mules are used to a large extent as pack animals, but they are imported from Argentina. Silkworms have been bred with success in some departments, and the cochineal insect is found wherever the conditions are favourable for the cactus.