The silence of day is succeeded by the “soundless tune” that fills the night. It surges up from below and shuts down from above. Pervasive as the murmuring of water, it spreads out through the night, pierced by a sudden brilliant squeak near at hand. With darkness settles a humming, booming, drumming, croaking, deafening uproar from thousands of diversified insect throats filling up every chink of space, each one crowding out the other. Insects here are not a miniature, far-off chorus, one ingredient of a summer night, but overwhelming, terrifying, absorbing the dark atmosphere.
Mysterious animals live in the depths of the ocean where no ray of light has ever pierced. They light the way for their own fishing, as the glow-worm is struck by its own brightness before seeing any other. Fire-beetles and phosphorescent caterpillars and flickering fireflies—little stitches of a shining thread in the soft, verdured blackness of the tepid night—make the primeval forest discernible.
The true life of the jungle begins with darkness and ends with light. As if the habitual gloom were not deep enough, jungle animals wait until night has enclosed them further to carry on their life activities, those weird creatures which lurk in the shade, primeval instincts always alert, living on suffrance in this land of vegetation. They have persisted since early geologic ages, the only remnants of their kind, haunting the nights from then until now. Dwarfs of a former age, growing constantly smaller and fewer and less important, they will dwindle through coming ages until zoölogical gardens can no longer be supplied, and their toothless skulls in glass cases will be the only evidence that they ever existed.
The antediluvian ant-eater hunches along on his stiff, curved claws, stopping now and then to rake out a crowded ant-hill, whose compact, crawling interior he cleans out with an efficient slash of his spiral tongue.
The giant armadillo, the glyptodon of former ages, developed a complete coat-of-mail by which his small descendant is still protected. He can open and shut the scales at will, hiding himself inside them. He trundles to and fro, burrowing out well-flavored roots. His voice is dull, without ring or expression. But his little shell is used as the bowl of a curious, three-stringed guitar from which natives can coax sweet sounds.
The tapir is another twilight animal, protected by his enormously thick hide. He snuffs about with his long snout, follows paths made by himself to the water, and sounds his queer whistle as alarm.
The cavernous croak of the violet-colored throat-bladder matches the twilight. The goat-sucker, with softly flapping wings, rises to greet the night, and from deep within the forest resounds the drawling cry of the sloth. His small, ghoulish face peers into the oncoming darkness.
Night settles. Bloodthirsty bats emerge, bright eyes flashing eagerly. Leaf-nosed vampires, whose empire is gloom, are prepared for their nightly bacchanale.
When utter blackness has obliterated the jungle, the carbunculo slinks slowly out of the thickets. “If followed, he opens a flap in his forehead from under which an extraordinary brilliant and dazzling light issues, proceeding from a precious stone; any foolhardy person who ventures to grasp at it is blinded, the flap is let down under the long black hair and the animal disappears into darkness. The Incas believed in him. The viceroys in their official instructions to the missionaries, placed the carbunculo in the first order of desiderata.”