1971] Willey & Willey — Populations of Grasshoppers 
349 
of the quadrat to the south or west of the line (see quad. No. 32). Mer- 
cator lines 285 km East and 4265 km North are printed also on PI. 2. 
The U.S. Geoglogical Topographic Maps were drawn from aerial photo- 
graphs taken between 3 September and 27 September 1955. The light colored 
areas are grassland, grey is chaparral and dark is forest. 
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