We moved through a deep quiet, broken only by occasional twitters or trills. We caught frequent glimpses of the creatures emitting the sounds as they fluttered among the branches of the vivid, unearthly trees. They resembled birds in a way, having feathered wings, but their bodies were lizard-like and covered with bright, rainbow-hued scales. And several times animals bounded from our path that looked like nothing so much as tiny deer. These seemed to be quite numerous. The vegetation gradually thinned out as the ground became increasingly rocky. Ahead of us loomed the rugged, precipitous ascent of the valley's upper end. Sandley stopped, peering about him. "This is the place." Abruptly he pointed. "There--the butterfly-creatures! See them?" Pearce and I followed the direction of his finger. Against the mottled gray wall of the ascent, a number of bright shapes fluttered. As we watched, they drifted slowly toward us, circling aimlessly. We were able presently to see them in clearer detail. I stared as a realization of something strange struck into me. I heard Pearce gasp. For the butterfly-creatures were not insects, or anything even remotely resembling them. Nor were they a strange form of animal life. They were _things_, utterly alien and weird. * * * * * Imagine large, irregularly-shaped pieces of thin paper fluttering through the air, each being creased in the middle, the two halves flapping like the wings of a butterfly. The things were remarkably like that. But they were alive in some incredible way, and their actions seemed purposeful, directed. They looked delicate and fragile, almost unsubstantial, mere veils of prismatic light. And they possessed a bizarre, unearthly beauty. As they circled high overhead, occasionally dipping toward us in what might have been curiosity, their wings shimmered and pulsed in a hypnotic play of rainbow color. The butterfly-creatures--to call them that for want of a better name--did not come near us. They continued to spiral high overhead, as though we at once attracted and puzzled them. Sandley unlimbered his camera and began taking pictures of the things. Pearce and I, recalling the motive that had brought us there, gradually moved away, searching the ground for promising bits of rock and crystal. We were intent on our quest, and wandered quite a distance. Before long, we found ourselves among the tumbled boulders at the foot of the ascent.