Toward dusk all the Swallows of the world—or so it appears—fly past in loose bands or singly, northward toward the eta bush to roost, hundreds and thousands of them—Red-breasted,[123] Banded,[118] Barn,[121] Variegated[119] and Tree[120] Swallows with scores of the Gray-breasted Martins.[122] Then the fishers of the savanna appear, looking whiter and more ghostly than ever, against the dark clouds; flock after flock flapping silently over: a score of Egrets[32] in an irregular line, then a dozen more smaller troops; Wood Ibises[28] higher up and beating heavily, then—and our pulses quicken—a half dozen great Jabirus[30]—slowly throbbing toward the sunset. The Ducks prefer the river, and above the fluid tide a living river of birds sets upstream, hosts passing until long after dark. We paddle in the early dusk to mid-stream and the whistling stream of Ducks curves gracefully upward, descending again when beyond us. As we go up or down river, we find the bend always overhead; when we leave the river, the host resumes its horizontal flow again. Faintly from behind the house, from the edge of the distant eta bush itself, comes in the evenings a low sound, gaining in volume until the syllables may be framed to human speech—_Mo-hóo-ca! Mo-hóo-ca!_ and we are listening to the evening call of the Horned Screamer,[41] a bird known to us only from books. The night sounds from the lagoon are full of mystery. Sea-cows souse and roll in the river and apparently at the very landing. Otters play and cough and utter gasping sighs which make one’s flesh creep until we learn what they are. The legend of the Warracabra Tigers, which Waterton and all after him recount, may well have had its origin in these great river mammals, who are noisy, fearless and sometimes reach a length of six feet. A beautiful skin which I brought home measures five and a half feet from nose to tip of tail. Water-haas, or capybaras, probably add their share to the confusion, but the major part of the medley is due to crocodiles, who wait until night before beginning their active, noisy business of life, which, be it concerned with food, mate or play, requires a vast deal of splashing and bellowing. This latter is a deep abrupt roaring like the final roars of a lion’s cadence. An eight-foot crocodile was shot in the lagoon a few days before, or rather shot at, as the beast seemed to be none the worse. [Illustration: FIG. 159. LAGOON BETWEEN ABARY ISLAND AND RIVER.] Small wonder that, when we consider snakes, crocodiles, otters and voracious fishes, that the gentle Vicissi Ducks prefer the safer vegetation of the marsh itself! The real birds of night were few—but with voices weird and awesome, in perfect harmony with this unpeopled waste. A pair of Parauque-like beings who in uttering liquid accents reiterated their names, mingled with the ever tragic toned questioning of another Goatsucker, pleading with us to end his agonized uncertainty—_Whó-are-yoú? Whó-are-yoú?_