al travel is full of interesting and difficult
problems, and not the least interesting nor the least difficult is the
question of just how they find their way to and from various places.
Many naturalists tell us that these animals are led by inherited
instinct along the migration lines followed by their forefathers. But
even if this were true, what made them originally follow such a course?

Wild horses when travelling always have a leader as well as several
sentinels for each herd. By some unknown code this leader makes known
his wishes and directs the movements of the herd. No human army could
have greater order or more perfect obedience to commands; and under him
there is absolute unity by means of which the carnivorous animals, such
as the wolf, the jaguar, and the puma, are repelled. Wild deer
invariably have a leader, and while we do not know how he obtains his
position, nor how he directs his followers, we do know he is highly
successful in his efforts.

No act in the animal world bespeaks more intelligence than that of
placing sentinels, especially during a journey. Horses show striking
skill and ingenuity in the choosing and placing of their sentinels. Any
one who has been fortunate enough to have seen them travelling in the
forests of South America, where the wild horses are gregarious, and
travel in herds of five hundred to a thousand, has noticed that
sentinels are always stationed around the herd. These animals are not
well prepared for fighting, and experience has taught them that their
greatest safety is in flight, and so, when they graze or sleep,
sentinels are always on the look-out for enemies. If a man approaches,
the sentinel at first walks toward him, as if to make sure what the
enemy is, and what he desires, if the man goes nearer to the herd, the
sentinel neighs in a most peculiar tone. Immediately the herd is
aroused, and gallops away, not in confusion, but perfect order, as
though its members were human soldiers.

The same is true of the white-legged peccaries, so plentiful in Guiana.
They congregate by the thousands, choose a leader whose position is
always at the front, and travel for hundreds of miles through the great
forests. If they come to a river, the leader halts, as if to make sure
that all is well for crossing, then he plunges into the water and is
followed by his immense army. The sureness of the leader would suggest
that he has been over the same route many times before--perhaps t