to the mules. It was trying to the nerves, for while
on one side rose a perpendicular wall of rock, on the other the
precipice went sheer down for several hundred feet, with a roaring
torrent at the bottom. Wild rocks were before and above us, trees and
shrubs, however, growing out of every crevice and on each spot where
soil could rest, while behind spread out a wide extent of forest, amid
which we could distinguish the river winding its way to the Pacific.
Few birds or beasts were to be seen--the monkeys and parrots we had left
below us; gallinazos, or black vultures, were, however, still met with,
as they are everywhere throughout the continent, performing their
graceful evolutions in the air, wheeling round and round without closing
their wings, in large flocks, above the watery region we had left. The
black vulture (_Cathartes atratus_), which closely resembles the
well-known turkey buzzard in habits and appearance, performs, like it,
the duty of scavenger, and is protected therefore by the inhabitants of
all parts of the country. It may be distinguished from the latter by
the form of the feathers on the neck, which descend from the back of the
head towards the throat in a sloping direction; whereas the turkey
buzzard has a frill of them completely round the throat. The head and
part of the neck of the black vulture are destitute of feathers, and are
covered with a black wrinkled skin, on which a few hairs only grow.
"See, what grand fellows are these!" exclaimed Arthur. I gazed up. On
a rock close above us stood a couple of large birds, which were
unmistakably vultures.

"Dreadful-looking creatures," cried Ellen. "They make me shudder. They
seem as if preparing to pounce down on some little innocent lambs to
carry them off."

"It would prefer a dead mule, I suspect," observed John. "Like other
vultures, it is not nice as to the nature of its food. It is called the
King of the Vultures (_Sarcoramphus papa_), properly so, for it is the
strongest and bravest of the vulture tribe though inferior in size to
the condor. Observe its head and neck, brilliantly coloured with
scarlet and yellow to make amends for the want of feathers. On the
crown of its head, too, is a rich scarlet patch. Close to the eye there
is a silvery blue mark, and above it part of the skin is blue and part
scarlet. The bill is orange and black, and those curious lumps or
carbuncles on its forehead are rich orange. At the lower par