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heights) could be calculated for any arbitrary water level, but no monthly values could yet be asaigned since there were no monthly stage data. However, current velocities could be estimated through the entire range of water level, the longitudinal slope could be measured, and Manning's n could be readily calculated. With this value, current velocities for all water levels could be computed. Then a regression line was calculated which related current velocity to the cross-sectional area of that portion of the channel occupied by water, with the velocity/area relation calculated for each of many small increments of water level change (fig. 2). The slope and intercept of the regression line are then characteristic of the type of channel and water regime at that site. Now, turning again to the literature sites, the same process was used to obtain regression lines which charac- terize those si tes. 17. In topographically and climatically similar regions, streams of equivalent size (or discharge) will exhibit similar channel geometries if their discharge regimes are similar. By extension, streams which exhibit similar water level/discharge (or water level/current velocity) relations will exhibit similar discharge (or stage) regimes. The procedure was then to match the slope and intercept values of the velocity/area regression line of each field site with its closest equivalent among the velocityfarea re- gression lines of the literature sites; when a close fit was found, the stage regime of the literature site was assigned to the related field site. With stage relations thus assigned, the various factors describing the field sites could be readily calculated for each month. Thus, all geometric and hydro- logic factors could be completed for both field and literature sites (fig. 3). 18. The digits in the "Stage" columns in the part of fig. 3 labelled "Factor Complex" are arranged in the following left-to-right sequence: Depth, water width, left bank height, right bank height, left bank angle, right bank angle, velocity. The numerical value of the digits correspond to the class of the respective factor in Table 2. For example, the number 3 in the upper left corner means the water depth for the mean high stage conditions for 15 January in water depth class 3, i.e. > 100-200 em. 19. The soil strength (cone index value) and vegetation factors were, as previously mentioned, completely absent from the literature site descrip- tions and were, of course, available for the field sites only at the time the site was visited by the field team. Since vegetation structure is not time-dependent (at least on the scale of time considered for this work) the factor values for all sites remained a constant throughout the year. Factor descriptions were obtained directly from field data for the field sites, while photo interpretation techniques were used to provide these data for the literature sites. 18