Of the three geographical groups of this family, the most important is found on the south bank of the Amazon, from the Jutahy east to the Huallaga west, on both banks of the Ucayali from its mouth to parallel ro° and the right bank of its tributary, the Urubamba, in the entire basin of the Upper Jurua and the sources of the Purus. The second group covers the basin of the Inambari, while the third group holds the banks of the Mamore, the Beni and the Madre de Dios between 9° 15' and 12° 3o' latitude and 64° 45' to
3o' longitude.
This family probably represents one of the oldest elements in South America and extends over the whole of the southern half of the Brazilian plateau reaching Xingu on the west and the Atlantic coast on the east, whence its speakers were expelled by Tupi-Guarani in the 15th century. The classification of Ge speech has yet to be accomplished and is one of the most urgent linguistic tasks awaiting the Americanist.
The first or eastern of the three geographical groups of the Tukano family covers the basins of the Uaupes, Curicuriary and Apaporis. The western group occupies the entire basin of the Napo from its junction with the Amazon up to the mouth of the Aguarico, along the latter river, along the Putumayo from its source to its junction with the Yaguas, along the upper Caqueta to about the 74th degree longitude. The northern group is found at the sources of the Manacacia, a tributary of the Meta.
An immense area south of the Amazon between 72° 3o' and 62° 3o' longitude and between 4° and 9° latitude is occupied more or less continuously by this family.
Like the Ge group the speakers of the Puinave languages are among the most primitive peoples of South America and represent a very ancient element of the population. The Puinave are found in the basin of the Inirida and the nomadic Maku between the Rio Negro and the Yapura, between 69°3o' and 61° 45' longitude.
The Guaykuru languages are spoken by a series of tribes along the banks of the Paraguay, the Parana and their tributaries and in the Chaco, e.g., Mbaya-Guaykuru, Guachi, Payagua, Toba, Mokovi, Abipon.
In the lesser Chaco a compact group is formed by the following: Mataguayo, Matako, Vejoz, Choroti, Ashluslay. etc.
All over the western portion of South America are spread isolated languages, such as Jirajara, Timote, Yaruro, Otomak, Guahibo, Saliba, Maku, Shiriana, Auake, Kaliana, Guarauno in Venezuela or on the borders of Brazil and Venezuela; Koche, Kofane, Zaparo, Chirino, Kahuapana, Cholona, Amuesha, Tuyuneiri, Leko, Moseten, Yurakare, along the eastern slopes of the Andes and the upper tributaries of the Amazon from southern Colombia to Bolivia ; Witoto, Yuri and Mura on the upper and middle Amazon ; Mobima, Kayuvava, Kanichana, Ito nama, Chapakura, Mashubi, Huari, Nambikuara, Karadja, Trumai, Bororo, Chiquito, Guato, Samuku, Maskoi, Enimaga and Shavante in central and southern Brazil, in eastern Bolivia and in Para guay; Kariri in eastern Brazil; Charrua formerly spoken in Uruguay; Vilela-Chulupi, Sanaviron, Allentiak, Het and Puelche in the Chaco and in the Argentine Plain.
Of the three southernmost languages of the continent, Alakaluf, Yahgan and Chon, only the last, now spoken by the Patagonians or Tehuelche of the Argentine Pampa, and by the Ona in Tierra del Fuego, has been identified and is found to belong in respect of vocabulary to Australian languages. The migration of Australians to America must have taken place via the Antarctic during the post-glacial optimum when the climate of those regions was sensibly more favourable than now, a period counted by geologists as not less than 6,000 years distant. (Rivet, Bulletin de la Societe de linguistique de Paris, t. xxvi. 1-2, pp. 23-63, 1925 ; Compte-rendu sommaire des seances de la Societe de bio-geographie, Paris, 3eme annee, no. 18, seance Feb. 19, 1926.) Although links have been established with Australia and in the north with Malayo-Polynesian Australasian (e.g., the Hoka group) and with Sino-Tibetan (e.g., the Na-Dene group), linguists have failed to prove any relationship between the languages of North and of South America or with those of Central America. Informa tion is also needed about the dying languages before they have completely disappeared.
Les Langues du monde, by a group of specialists under the direction of A. Meillet and Marcel Cohen (1924) ; W. Schmidt, Die Sprachenfamilien der Erdkreise (1926).