Most constellations are patterns of stars. A smaller family of figures, read mainly in the southern hemisphere where the galactic centre rides high, works the other way: the figure is a dark shape, a cloud of interstellar dust silhouetted against the glow of the Milky Way, and the band itself is the canvas the figure is drawn on. The Andean sky holds the fullest recorded set.
The Yacana, the llama, is the largest of them, rising with two bright stars for eyes; Machacuay the serpent and Yutu the tinamou follow it in a fixed procession along the river Mayu, and Andean observers time the year by which animal stands where. Aboriginal Australia reads the Emu in the Sky the same way: the head is the dense dark patch Western astronomy calls the Coalsack, beside the Southern Cross, and the neck and body run down the length of the band.
None of these figures contains a single star. The atlas records each of them as a constellation in its own register, linked to this page as figures contained in the Milky Way, because the band is what makes them possible. Modern astronomy gives the shadows a cause without changing the observation: the dark shapes are lanes of dust in the galactic disc, dense enough to swallow the light of the stars behind them, the same material from which new stars condense.