Zone of wheat and oats on large scale. The Pampa is a tableland here (400 feet above sea-level), with clay overlying the limestone of the Tosca. The valleys are well marked.
Photograph by the Author.
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THE PAMPEAN PLAIN. TOAY, ON THE CENTRAL PAMPA (590 FEET).
The tableland, with a strong framework of limestone Tosca, is cut across by well-marked dry valleys which sink lower toward the east. At the edges of the valleys the sand is the prey of the winds. Here we are near the limit of the wheat belt.
Photograph by the Author.
Plate XV.
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