186 URSINE, OR HOWLING MONKEYS. 
CHAPTER XV. 
Journey across the Llanos, from Aragua to San Fernando. 
Mountains between the Valleys of Aragua and the Llanos—Their 
Geological Constitution—The Llanes of Caraccas—Route over 
the Savannah to the Rio Apure—Cattle and Deer—Vegetation 
—Calabozo—Gymnoti or Electric Eels—Indian Girl—Alligators 
and Boas—Arrival at San Fernando de Apure. 
From the chain of mountains which borders the 
Lake of Valencia toward the south, there stretches 
in the same direction a vast extent of level land, 
constituting the Llanos or Savannahs of Caraccas ; 
and from the cultivated and populous district of 
Aragua, embellished with mountains and rivers and. 
teeming with vegetation, one descends into a parch- 
ed desolate plain, bounded by the horizon. On 
this route we now accompany our travellers, who 
on the 6th March left the valleys of Aragua, and 
keeping along the south-west side of the lake, pass- 
ed. over a rich champaign country covered with cala- 
bashes, water-melons, and plantains. The rising of 
the sun was announced by the howling of monkeys, 
of which they saw numerous bands moving as in 
procession from one tree to another. These crea- 
tures (the Sima ursina) execute their evolutions 
with singular uniformity. When the boughs of two 
trees do not touch each other, the leader of the party 
swings himself by the tail upon the nearest twigs, 
