Even as he spoke, the songster itself fluttered up into the air, a brown bird with a white throat, and tail and wings broadly banded with the same color. Up and up it soared, and its notes chimed like a golden bell as its incomparable song drifted down through the moonlight to those listening below. Then on glistening wings the spent singer wavered down like some huge moth and disappeared in the dark of the thicket. In the silence that followed, Will drew a deep breath.

"I'd have traveled around the world to hear that song," he half whispered.

Professor Ditson nodded his head understandingly.

"Many and many an ornithologist," he said, "has come to South America to listen to that bird and gone away without hearing what we have heard to-night. Between his own two songs," went on the professor, "I counted the notes of seventeen other birds of both North and South America that he mimicked."

They paddled gently toward the shore, hoping to hear the bird again, but it sang no more that night. As they neared the beach, the moonlit air was heavy with the scent of jessamine, fragrant only after darkness, and the overpowering perfume of night-blooming cereuses, whose satin-white blossoms were three feet in circumference. Suddenly, just before them, the moon-flowers bloomed. Great snowy blossoms five inches across began to open slowly. There was a puff of wind, and hundreds of them burst into bloom at once, glorious white salvers of beauty and fragrance.

"Everything here," said Will, "seems beautiful and peaceful and safe."

Professor Ditson smiled sardonically. "South America is beautiful," he said precisely, "but it is never safe. Death and danger lurk everywhere and in the most unexpected forms. It is only in South America," he went on, "that you can be eaten alive by fish the size of small trout, or be killed by ants or little brown bats."

Jud listened with much scorn. "Professor," he broke out at last, "I don't take much stock in that kind of talk. Your nerves are in a bad way. My advice to you is—"

What Mr. Judson Adams's advice was, will never be known, for at that moment a dreadful thing happened. Into the beauty of the moonlight, from the glassy water of the bay soared a shape of horror, a black, monstrous creature like a gigantic bat. It had two wings which measured a good twenty feet from tip to tip, and was flat, like an enormous skate. Behind it streamed a spiked, flexible tail, while long feelers, like slim horns, projected several feet beyond a vast hooked mouth. Like some vampire shape from the Pit, it skimmed through the air across the bow of the canoe not ten feet from where Jud was sitting. The old trapper was no coward, but this sudden horror was too much even for his seasoned nerves. With a yell, he fell backward off his thwart, and as his legs kicked convulsively in the air, the monster came down with a crash that could have been heard a mile, raising a wave which nearly swamped the canoe. A moment later, the monstrous shape broke water again farther seaward, blotting out for an instant with its black bulk the rising moon.

"What kind of a sea-devil is that, anyhow?" queried Jud, shakily, as he righted himself, with the second crash of the falling body still in his ears.