Of archaeological evidence from the Valsequillo region, Puebla, Mexico / Cynthia Irwin-Williams -- The origin of Zea mays / George W. Beadle -- Obsidian exchange networks: inferences and speculation on the development of social organization in formative Mesoamerica / Jane Wheeler Pires-Ferreira -- Shell exchange networks in formative Mesoamerica / Jane Wheeler Pires-Ferreira -- Mossbauer spectral analysis of Olmec iron ore mirrors: new evidence of formative period exchange networks in Mesoamerica / Jane Wheeler Pires-Ferreira and Billy Joe Evans -- The significance of the 'epiclassic' period in Mesoamerican prehistory / Malcolm C. Webb -- Ports of trade in Mesoamerica: a reappraisal / Frances Frei Berdan -- The ancient Maya in light of their ethnographic present / James C. Gifford -- Ideas concerning Maya concepts of the future / James C. Gifford -- Ethnographic realities of Mayan prehistory / Jeffrey C. Howry -- Mesoamericans as cultural brokers in northern New Spain / John Hobgood and Carroll L. Riley -- Toward the reconstruction of the Olmec mythological system / R.V. Kinzhalov -- Maya and Teotihuacan traits in classic Maya vase painting of the Peten / Jacinto Quirarte -- The Aztec system of writing: problems of research / Joaquin Galarza -- The deciphering of glyphs representing Mexica governmental titles / Horacio Corona Olea -- The Aztec day names / Herbert Landar -- The relationship between painting and scripts / Jorge Elliott -- Petroglyphs of the Antilles / Ripley P. Bullen -- Contribution to the study of cultural sequences in the central area of Costa Rica / Carlos H. Aguilar.