VALLEY FILLING BY INTERMITTENT STREAMS 219 



valley. From both the pictures and the map we see that through- 

 out the whole valley we have steps and above each step the valley 

 bottom is flat floored. Only at one point in the valley, just below 

 the forty-five-foot point, is it V-shaped. 



The flat floor indicates filling. This is best seen perhaps in 

 Fig. 3. This view also gives other convincing evidences. The 

 sharp angle between the valley sides and bottom is a good evi- 





Fig. 2. — The lower part of the valley. In this part there is a continuous flow of 

 water throughout the year, it being below the water table. The water course is much 

 choked with grass. One step may be seen just this side of the tree, a walnut, in the 

 valley bottom near the middle of the picture. On the map the location of the tree 

 is designated by W. T. 



dence, the buried "feet" of the trees is another, and the most 

 convincing of all is the position of the stump in the face of the 

 bank or cliff. Just above the roots, where the surface of the 

 ground is found with most trees, is a dark layer of soil about three 

 inches thick. This marks the level of the valley bottom before 

 filling. The view also shows that active erosion is going on at this 

 point causing the step to recede up stream. This recession takes 

 place only during and after rain storms and wet weather in the 

 spring. The material taken from here goes to build up the steps 

 in the lower part of the valley. 



