The Stratigraphic data on some of the Peruvian samples provide a fairly good basis for evaluating the radiocarbon date measurements in relation to each other. The accompanying chart (Fig. 1) was prepared to clarify what is bound to be tedious reading. On it the plotting of the radiocarbon dates is obvious. The insertion with them of sectional profiles of midden excavations may be confusing, but does show where the tested material was found. In one instance (382), although the tested sample did not come from this midden, it belongs chronologically at the level indicated. Knowledge of the nature of the structure between the various layers gives us further means of assessing the results. Thus it is possible to compare the date blocks, as we might call the total plus and minus time span, and to point out which portions cannot be reconciled and are therefore impossible and which portions are improbable. The remaining segments mark the periods within which the actual dates are most likely to fall.