extra-natural, in that low level plain, so green and fresh and snaky,
where my horse's hoofs had made no sound--a place where no man dwelt,
and no cattle pastured, and no wild bird folded its wing. And the
serpents there were not like others--the mechanical coiled-up thing we
know, a mere bone-and-muscle man-trap, set by the elements, to spring
and strike when trodden on: but these had a high intelligence, a lofty
spirit, and were filled with a noble rage and astonishment that any
other kind of creature, even a man, should venture there to disturb
their sacred peace. It was a fancy, born of that sense of mystery which
the unknown and the unusual in nature wakes in us--an obsolescent
feeling that still links us to the savage. But the simple fact was
wonderful enough, and that has been set down simply and apart from all
fancies. If the reader happens not to be a naturalist, it is right to
tell him that a naturalist cannot exaggerate consciously; and if he be
capable of unconscious exaggeration, then ho is no naturalist. He
should hasten "to join the innumerable caravan that moves" to the
fantastic realms of romance. Looking at the simple fact scientifically,
it was a case of mimicry--the harmless snake mimicking the fierce
threatening gestures and actions proper to some deadly kind. Only with
this difference: the venomous snake, of all deadly things in nature, is
the slowest to resentment, the most reluctant to enter into a quarrel;
whereas in this species angry demonstrations were made when the intruder
was yet far off, and before he had shown any hostile intentions.

My last case--the last, that is, of the few I have selected--relates to
a singular variation in the human species. On this occasion I was again
travelling alone in a strange district on the southern frontier of
Buenos Ayres. On a bitterly cold midwinter day, shortly before noon, I
arrived, stiff and tired, at one of those pilgrims' rests on the pampas
--a wayside _pulperia,_ or public house, where the traveller can procure