y a common motive. Manuel ran ahead in his excitement, turning
to shout to me, and then to point toward the wavering, swelling, white
streams. I hurried after him, to that end of the island where we had
landed, and I found the colony of boobies in a state of great
perturbation. All were squawking, flapping wings, and waddling
frantically about. Here was fear such as had not appeared on my advent.

Thousands of boobies were returning from deep-sea fishing, and as they
neared the island they were met and set upon by a swarming army of
_rabihorcados_. Darting white and black streaks crossed the blue of sky
like a changeful web. The air was full of plaintive cries and hoarse
croaks and the windy rush of wings. So marvelous was this scene of
incredibly swift action, of kaleidoscopic change, of streaking lines and
curves, that the tragedy at first was lost upon me. Then the shrieking
of a booby told me that the robber birds were after their prey. Manuel
lay flat on the ground to avoid being struck by low-flying birds, but I
remained standing in order to see the better. Faster and faster circled
the pursued and pursuers and louder grew the cries and croaks. My gaze
was bewildered by the endless, eddying stream of birds.

Then I turned my back on sea and beach where this bee-swarm confused my
vision, and looked to see single boobies whirling here and there with
two or three black demons in pursuit. I picked out one group and turned
my glass upon it. Many battles had I seen by field and stream and
mountain, but this unequal battle by sea eclipsed all. The booby's
mother instinct was to get to her young with the precious fish that
meant life. And she would have been more than a match for any one thief.
But she could not cope successfully with two fierce _rabihorcados_; for
one soared above her, resting, watching, while the other darted and
whirled to the attack. They changed, now one black demon swooping down,
and then the other, in calculating, pitiless pursuit. How glorious she
was in poise and swerve and sweep! For what seemed a long time neither
_rabihorcado_ touched her. What distance she could have placed between
them but for that faithful mother instinct! She kept circling, ever
returning, drawn back toward the sand by the magnet of love; and the
powerful wings seemed slowly to lose strength. Closer the _rabihorcados_
swooped and rose and swooped again, till one of them, shooting down like
a black flash, struck her in the