General Editor's Preface -- Preface -- PART ONE: EARLY MAN IN MESOAMERICA AND THE AGRICULTURAL BASIS -- Introduction -- Summary of Archaeological Evidence from the Valsequillo Region, Puebla, Mexico -- The Origin of Zea mays -- PART TWO: EXCHANGE NETWORKS -- Introduction -- Obsidian Exchange Networks: Inferences and Speculation on the Development of Social Organization in Formative Mesoamerica -- Shell Exchange Networks in Formative Mesoamerica -- Mössbauer Spectral Analysis of Olmec Iron Ore Mirrors: New Evidence of Formative Period Exchange Networks in Mesoamerica -- The Significance of the "Epiclassic" Period in Mesoamerican Prehistory -- Ports of Trade in Mesoamerica: A Reappraisal -- PART THREE: ETHNOGRAPHIC CONTRIBUTIONS TO PREHISTORY -- Introduction -- The Ancient Maya in Light of Their Ethnographic Present -- Ideas Concerning Maya Concepts of the Future -- Ethnographic Realities of Mayan Prehistory -- Mesoamericans as Cultural Brokers in Northern New Spain -- PART FOUR: PAINTING, HIEROGLYPHS, CERAMICS, AND MYTHOLOGY -- Introduction -- Toward the Reconstruction of the Olmec Mythological System -- Maya and Teotihuacán Traits in Classic Maya Vase Painting of the Petén -- The Aztec System of Writing: Problems of Research -- The Deciphering of Glyphs Representing Méxica Governmental Titles -- The Aztec Day Names -- The Relationship Between Painting and Scripts -- Petroglyphs of the Antilles -- Contribution to the Study of Cultural Sequences in the Central Area of Costa Rica -- Biographical Notes -- Index of Names -- Index of Subjects.