130 H. E. Gregory — Geologic Reconnaissance of the 



maturity. A glance into the Apurimac canyon (fig. 5) shows 

 that the present valley form has by no means been attained by 

 regular progressive growth within a single cycle. At least two 

 rock benches and two alluvial terraces occupied by small 



Fig. 4. 



Fig. 4. View from SeSor Calvcrs garden, looking northwestward, down 

 the Mollemolle into the Apurimac canyon. 



Andean villages mark the valley wall, — -facts which indicate 

 an involved physiographic history whose episodes await inter- 

 pretation. 



The higher mountain valleys are flat-floored, wide open, 

 bounded by steeply-sloping walls which join the plateau sur- 

 face at an abrupt angle. To these evidences of glaciation may 



