158 SOUTH AMERICA 



hollows, mostly shallow and devoid of outlet, collect 

 the waters, and dot the surface of the boundless plain 

 with innumerable marshes, brackish or salt, or merely 

 damp troughs ; the soil is a stoneless, fine sand, or sandy 

 and powdery loess; the rivers are often saline, and 

 thanks to the alternations of droughts and heavy down- 

 pours, the soil is caked hard and rendered impervious. 

 Winters are short and comparatively mild, though 

 distinctly felt ; daily ranges of temperature are stronger 

 than in the north, and nightly dew is abundant. 



The carpet is made of separate dense tufts of stiff 

 grasses, not in a close mat, but showing the ground in 

 the intervals. According to the nature of the numerous 

 grasses melica, stipa, aristida, andropogon, pappo- 

 phorum, panicum, paspalum, and others the aspect 

 varies slightly. Herbs, mostly evergreen perennials 

 with small leathery leaves, are interspersed among the 

 grasses ; bulbs are not as abundant as might be expected, 

 and annuals are few. Trees are excluded but for occasional 

 and solitary ombus (phytolacca) which grow near the 

 houses. Rivers flow either between sandy banks or tall 

 hedges of gynerium, pampas-grass and reeds, forming 

 what is called ' pajohales '. In the slightly undulating 

 pampa, the moister hollows or shallow canadas are lined 

 with a softer turf, and denser swards mixed with 

 various low, succulent plants and flowers. 



The changeful albeit monotonous aspect of the pampa 

 has been thus described : ' Coal black in spring when 

 the old grass has been burned ; bright bluish-green when 

 the young leaves sprout ; later on brownish-green, the 

 colour of the mature grass ; finally at the flowering 

 time when the silvery white spikes overtop the grass, 

 over wide tracts it seems like a rolling, waving sea of 

 liquid silver.' 



