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23 called upland channels; 2) tho"e that extend up to the cliffs are called cliff channels; 3) those that originate on the piedmont are .- W called piedmont channels; 4) those that are tributaries to any of the -.J .... first three types and originate on the piedmont are called tributary- basin channels; 5) those that are smaller tributaries within the tribu- tary basins are called tributary channels; and 6) those that are formed on the hillslope s are called rills. Channel and basin development appear to be analogous to rill formation. The similarities between these channels and the erosional development of rills were readily identified based on "tudies conducted by Mosley (1972). Conclusions offered by Mosley that are pertinent to this analogy are: 1) rills are formed by recession of knickpoints or headward erosion; 2) larger catchments are relatively more elongated than smaller catchments; 3) rill drainage density is lower in larger basins; and 4) rills are roughly parallel on straight slopes, and they, converge on concave slopes. Rills in the Mancos Shale badlands have been studied by several author", including Schumm (1964), Lusby, et al. (1971), Howard \ (1972), and Sunday (1979). However, the analogy between rill develop- ment and the overall channel system has not been made. The analogy is important in that it indicates that the surface of the piedmont is relatively steep and that rill-type erosion is the dominant erosional process in the area. Rills identify locations of rapid erosion. Since the area is com- posed of channels that appear to have the same genetic character of rills, the analogy between the channel system and rills, in terms of rapid erosion, can be inferred. Therefore, whereas rills have been ---:=, .1