The Indians, to whom the preparation of these heads is traced, are scattered over a wide tract of country on the eastern side of the Andes. They are known under the general designation Macao, the name of the region they inhabit—a designation which includes the Jivaros, Pastazas, Mendes, Tumbas, and more than twenty other tribes. Early brought into contact with the first Spanish invaders, they suffered much at their hands. Many references to them occur in the history of the Spanish settlers. Their appearance, social habits, and superstitious practices have much prominence given to them in the recent literature of South American travel. At present I limit my remarks mainly to the specimens of “shrunk” or reduced heads now before us. They are from several points of view remarkable, and raise several questions of great ethnological interest, but trustworthy references to them are comparatively few. Indeed, the only sources of information worth mentioning are a communication by Mr William Bollaert, F.R.G.S., to the Ethnological Society of London, 1860, and another, by Sir John Lubbock, to the Anthropological Institute of Great Britain in 1873. The former is entitled “On the Idol Human Head of the Jivaro Indians in Ecuador;” the latter, “Note on the Macas Indians.” In Mr Bollaert's paper special attention is given to a specimen obtained by M. José Felix Barriero, of the Secretariat of the Provincial Government, Quito, and sent by him to Don R. de Silva Ferro, Chilian Consul, London. This specimen was placed in the Ecuador Court of the International Exhibition, 1862. Sir John Lubbock's paper is devoted chiefly to a general description of the Macas Indians.