THE ANDES 163 



from the hottest to the coldest, and from the most arid 

 to the dampest regions, the cordillera of the Andes 

 practically summarizes the vegetation of the whole 

 world ; there is scarcely a form of plant life that is 

 not represented on that mightiest of mountain-ranges. 

 A powerful barrier athwart the path of the winds, 

 it is abundantly watered, now on one side, now on the 

 other, exhibiting nearly everywhere the opposite extremes 

 on eastern and western slopes. Under the equator, and 

 farther north, the benefit of the rain-belt extends in 

 fairly equal measure to both sides, so that the northern 

 range as far south as Guayaquil is under the influence 

 of regular and sufficient precipitations and shows no 

 striking contrast. Farther south, down to 30° S., the 

 eastern slopes are still well watered, though the western 

 side experiences extreme drought ; then for a short 

 interval of about 10 degrees of latitude, under warm 

 temperate conditions, both sides are about equally dry. 



In the southern domain of the westerlies, however, 

 the Pacific slopes become very moist, while the east 

 remain arid, and are not admitted to a share, limited 

 though it be, in the western rains before reaching 48° 

 to 50° S. 



Eastern Andes. The Montana. This name may be 

 applied to the vast crescent or amphitheatre of slopes 

 which define the Amazon valley on the west and extend 

 from Venezuela to the Argentine border, i.e. to the 

 Tropics; locally it is restricted to the Peruvian and 

 Bolivian portions. 



The Amazon selva rises up the slopes, almost un- 

 changed, to 4,000 feet or so, under the same conditions 

 of an excessive and uniform rainfall and heat. It is 

 followed higher up by a zone of rain-forest, with a 

 cooler, though scarcely less rainy climate, and exhibits 



M 2 



