Growing knowledge of cultural sequences in Mesoamerica and in Peru has caused archaeologists interested in correlating these areas and explaining the derivation of various traits to look longingly at the little-known intermediate region occupied by Ecuador and Colombia. In the fall of 1954 an invitation by Emilio Estrada, Director of the Museo Arqueologico “Victor Emilio Estrada” in Guayaquil, Ecuador, gave us the opportunity to make a brief survey and to excavate stratigraphically a few sites in the Guayas Basin on the central coast of Ecuador (Fig. 1). One of the sites excavated (R-B-l: La Chorrera) and two included in the survey (R-B-2: Al Frente el Tejar and G-D-8: 5Jaupe) produced potsherds and other artifacts of types that have been classified as belonging to the Formative period in Middle America and Peru.