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- 31 - cally, have relief of several tens of feet, and lengths of many hun- dreds of fee~., The ridge features are roughly parallel to the contour of the slope, and the scarps occur both parallel and at low to moderate angles to the contours. The generalized slope of the area is in the range of 40% to 60%, but is much steeper locally on the scarp and ridge features described above. These local topographic features, in general, do not show on the 7~' quadrangle map because of the overall steepness of the slope and the 40 foot contour interval. The larger scarps of this area can be seen on all of the various sets of aerial photographs used, but the complex of ridges could be seen well only on the very low altitude aerial photos. Our geologic interpretation of the history and development of this slope assumes that in the past, it has probably been a simple talus slope. However, at the present time (and for some time in the past), the slope has experienced much more active movement than the normal accretion and creep of an active talus. It is our impression that the debris slope is currently undergoing a very accelerated type of mass movement similar to the movement of rock glaciers. Active rock glaciers (or rock streams as they are sometimes called) are common in the sur- rounding Crystal River area at slightly higher elevations. The sharp transverse ridges which extend parallel to the slope contour, or bend convexly in the downslope direction, and the coarse blocky rock debris of which the slope is composed are all very similar to rock glaciers of the area. The slope in question differs from the usual rock glaciers in that the rock debris is on an open slope rather than being contained between valley walls. In addition, the scarps and narrow depression features are not typical of rock glaciers we have seen.