Many factors contribute to the result that archaeological field research in Middle America is done, not, as generally in the United States, by many small expeditions from many institutions, but by a few organizations whose activities are mainly or entirely devoted to this region. In recent years the Mexican government, the assistance of which is now embodied in the Instituto Nacional de Antropología e Historia, the Carnegie Institution of Washington, and the American Museum of Natural History, have contributed the major part of such research. For several years past, the joint expeditions of the National Geographic Society and the Smithsonian Institution have taken an important part, and during the season of 1941–1942 three expeditions of the Institute of Andean Research, under the auspices of the Office of the Coordinator of Inter-American Affairs, carried on excavations in Middle America.

Like the other cultured peoples of Mexico and Central America, the Tarascans of the time of the Conquest had knowledge of the calendar. Indeed, in the Relation de Michoacán–an anonymous work which, as we shall later see, was written between 1540 and 1541, –are mentioned the names of thirteen Tarascan months, and for four of them the corresponding date in the Christian calendar is given. One more month, although not named, is said to have fallen on November 14.

In the lake region of the Valley of Mexico Nature and Man have combined to .produce radical changes in the character of the landscape. The giant elliptic bowl about forty-five miles wide by fifty-five miles long, which was formed during the elevation of the Mexican plateau, has been the stage of violent volcanic outbursts, followed by interludes of sedimentation. In geologically speaking recent times and, accordingly, since man made his appearance in the valley, sedimentation has been the dominating, if not sole factor. Owing to the fact that the Valley of Mexico has no natural outlet, the sediments brought down from the surrounding steep and high mountain ranges have accumulated in enormous quantities, forming a huge floor, over which the water from the mountain sides spreads in a shallow sheet. Since precipitation is often violent, and very irregularly distributed throughout the year, and since even evaporation under the strong tropical sun is too slow to prevent great quantities of water from remaining in the valley for a considerable time, the history of man in this region is a narrative of an endless struggle against the wet element. Even today the work is going on, although the tunnel outlet finished in 1900 has put a stop to inundations on a large scale. The colonial works have turned the lake bottom into an arid and salty desert, only partly covered by water.

El Tepalcate, an archaeologic site on a low flat peninsula situated just off the eastern shore of Lake Texcoco and near the town of Chimalhuacan, is the site described by Ola Apenes in the preceding article.

The excavations made at the site consisted of fifteen separate pits and trenches by which an attempt was made to find stratified materials and to determine the nature of the circular heaps of stone and the alignments of stone forming large rectangles which are the only architectural features visible on the surface of the site.

The Tepalcatepec Basin lies in west central Michoacán, about 250 miles west and south of Mexico City. It can be reached in the dry season by a road that leads south from Uruapan. The area covered is in a large valley (50 by 35 miles) limited on the south and west by the Rio Grande de Tepalcatepec and on the east by the Rio Marqués (Rio Cupatitzio). The northern limit is approximately the 700-meter contour where the foothills rise abruptly to the Sierras surrounding Mt. Tancítaro. This valley extends northwest some distance up the east side of the Rio Tepalcatepec.

During the summer of 1939, Dr. D. D. Brand led a party of graduate students in anthropology into Mexico with the purpose of studying the archaeology of the state of Michoacán and adjacent areas. After preliminary examination of the better known ruins in the northern part of this state, the party broke up and each individual went into a previously determined area in southern Michoacán or neighboring Guerrero or Mexico. The several resulting manuscripts are available in the Department of Anthropology at the University of New Mexico.

The Cordillera de Talamanca, the principal mountain range in southeastern Costa Rica, is a rugged chain which overlies, in part at least, an earlier volcanic mass, and is directly connected with the Chiriqui range of western Panama. The Pacific Ocean is, as the crow flies, a comparatively short distance from the Talamancan peaks. From the Rio Savegre in the southwest to the Rio Chiriqui Viejo in Panama runs a smaller parallel chain, known as the Pacific coastal range.

This paper concerns an excavation carried out by the author at a newly reported prehistoric site at Seba in British Guiana. The work done was very limited, being intended originally to be only exploratory, but by a fortunate chance an unusual and substantial cache of stone and pottery artifacts was found in one of the trial pits. This yielded a considerable amount of information about both the material and non-material culture of the site, thus lending more interest and value to the work than normally expected from excavations of such small extent.

Durante la Misión arqueológica que en 1936 me fué confiada por el Ministerio d: Educación Nacional, para hacer investigaciones sobre los recientes hallazgos de Tierradentro, hube de recoger en el Municipio de Inzá, Departamento del Cauca, trece cuentas de collar procedentes de una sepultura precolombina (PI. IX, a). Desde la primera observatión llamóme positivamente la atención el material de las cuentas que lo forman, una roca semi-transparente, de tonalidades violáceas y azulosas, poco consistente, de quebradura cristalina irregular y presentando filamentos alargados.

Maya history can be divided into four great periods; the formative, the initial series, the Mexican, and the Mexican absorption. The formative period (prior to A.D. 300) comprises the Mamom and Chicanel phases at Uaxactun and coeval phases found elsewhere in the central area (Petén, British Honduras, Chiapas, Tabasco, lower Motagua, drainage), the northern area (Yucatan, northern Campeche, Quintana Roo) and, as we shall see, the southern area.

In 1919, while exploring the basin of the Mariash or Pukcha River, one of the upper Amazon affluents, I found in Chavín de Huantar evidence of a culture that, up to then, had not been given due recognition. I proved that certain buildings and other products of aboriginal art found there belonged to a quite distinctive cycle of culture–that of the Chavín stone culture. Monolithic figures of serpents and felines, representing human heads, and stelae, obelisks, sundry utensils, and other objects decorated with incised or carved figures in plane, high or low relief, representing grotesque felines, serpents, fish, lizards and birds are the main features of this culture, whose area of diffusion had then been reconnoitered only in the provinces of Huari and Pomabama.