As one descended the slope the woods became thinner, and bushes, with occasional high trees, took the place of the forest. I could make good progress, therefore, and I could see without being seen. I passed close to the pterodactyl swamp, and as I did so, with a dry, crisp, leathery rattle of wings, one of these great creatures⁠—it was twenty feet at least from tip to tip⁠—rose up from somewhere near me and soared into the air. As it passed across the face of the moon the light shone clearly through the membranous wings, and it looked like a flying skeleton against the white, tropical radiance. I crouched low among the bushes, for I knew from past experience that with a single cry the creature could bring a hundred of its loathsome mates about my ears. It was not until it had settled again that I dared to steal onwards upon my journey.