re, there, and from
everywhere to take up their hygienic services where it has been left off
by the day scavengers.

If you were near an oasis in the desert at the close of day, you would
suddenly hear from the hot, barren sands a deep and peculiar sound. It
swells and grows as an approaching wind, growing louder and louder as it
comes nearer. Suddenly by the light of the camp fire, you see myriads of
horrid green eyes, like ghost torches in a graveyard, and hear gnashing
teeth, greedy in anticipation of the garbage you have thrown away.

These hyena hordes are frightfully ugly, but rarely dangerous to man.
They visit every oasis settlement in immense numbers, howling, yelping,
and fighting for any bit of offal they may find. Not a particle of
garbage remains. At the first sign of dawn, they disappear like rats
from a burning building, and seek their caves to digest their ignoble
banquets.

No human street-cleaner could ever excel their work. No matter how large
the garbage pile, no matter how many dead dogs, cats, and donkeys in a
village street, no matter how unspeakable the offal, it all vanishes as
completely as though it had been burned. Not a piece of bone, not a
single chicken feather remains. The natives have no fear of the hyena; a
small child armed with a stick can put to flight a dozen of them. They
are the lowest of cowards, and will flee from their own shadows.

[Illustration: THE MONGOOSE IS A SCAVENGER OF THE WORST TYPE, FEEDING ON
RATS AND MICE AND SNAKES, AND EVEN POULTRY.]

[Illustration: _American Museum of Natural History, New York_

DIPLODOCUS. THE PREHISTORIC ANIMALS, ALSO, UNDOUBTEDLY HAD THEIR
SCAVENGERS AND CRIMINALS.]

In spite of their valuable services, mankind hates the hyenas. This is
probably because of their absolute cowardice, for they will never attack
a living creature unless it is weak from illness. Sometimes they steal a
baby, never killing it outright, but carrying it away to their dens to
starve it to death before mutilating its body. If the courage of this
beast equalled his strength, he would be the despot of the desert. But
he is like his fellow workman, the jackal, cowardly to the last degree.

Neither of them ever attempts to put an enemy to flight by legitimate
means. They resort to fakery: one howls, and the other wrinkles his face
in great anger. The jackal's greatest asset and protection, when he
meets with an enemy, is bluff. He raises his ugly mane, lifts his
un