318 Bowman — Geologic Relations of the Cnzco Remains. 



middle portions of the same valley. The two photographs 

 were taken from the same point, so that the foreground 

 of the one may be identified in the other. The glaciated 

 portion of the valley is marked by a smooth and locally flat 

 floor, steep marginal walls (in places precipitous), a ground 

 moraine, and a flatter gradient than the unglaciated valley 



Fig. 12. 



Fig. 12. Middle sectiou of the Chacimayu valley showing alluvium on 

 valley floor and sides and the absence of glacial features. Looking down- 

 valley from station in which fig. 11 was taken. 



exhibits. Like the alluvium in the lower valleys, certain 

 features are here in process of destruction, and could not 

 have been made under existing conditions. The steep mar- 

 ginal walls are in process of dissection, and the resulting waste 

 is spread over the margins of the valley floor. The lower end of 

 the glaciated portion of the valley is being invaded by ravines 



