This is Number 10a of the series of correlation charts prepared under the auspices of the Committee on Stratigraphy of the National Research Council.1 It was originally intended to publish this chart with others dealing with the western interior of the United States and Canada, but it is now realized that those regions will be represented by several charts as large as the present chart, and that some of the charts may not be completed for several years. It seems best, therefore, to publish each chart as soon as it is ready.
Rather complete lists of references are given for the convenience of future workers. References dealing with the Greater Antilles are listed separately from those dealing with the Central American-Mexican region, as the two regions seem to have very different geologic histories.
In the correlation chart age equivalencies are shown by horizontal lining, hiatuses by vertical lining, and . . .