﻿Plate 
  7. 
  — 
  The 
  upper 
  reaches 
  of 
  the 
  

   Montana. 
  Top: 
  Southeast 
  corner 
  

   of 
  the 
  Castillo 
  at 
  the 
  famous 
  

   archeological 
  site 
  of 
  Chavin 
  de 
  

   Huantar, 
  Peru. 
  (Courtesy 
  Amer- 
  

   ican 
  Museum 
  of 
  Natural 
  History.) 
  

   Bottom: 
  In 
  the 
  Urubamba 
  drain- 
  

   age, 
  Junin, 
  Peru. 
  (Courtesy 
  Tru- 
  

   man 
  Bailey.) 
  

  

  - 
  

  

  