"The handmaiden is my own sister's child," he answered quietly. O'Keefe drew a long breath. "Uncle," he remarked casually in English, "meet the man who's going to be your nephew!" And thereafter he never addressed the green dwarf except by the avuncular title, which Rador, humorously enough, apparently conceived to be one of respectful endearment. For me a light broke. Plain now was the reason for his foreknowledge of Lakla's appearance at the feast where Larry had so narrowly escaped Yolara's spells; plain the determining factor that had cast his lot with ours, and my confidence, despite his discourse of mysterious perils, experienced a remarkable quickening. Speculation as to the marked differences in pigmentation and appearance of niece and uncle was dissipated by my consciousness that we were now moving in a dim half-light. We were in a fairly wide tunnel. Not far ahead the gleam filtered, pale yellow like sunlight sifting through the leaves of autumn poplars. And as we drove closer to its source I saw that it did indeed pass through a leafy screen hanging over the passage end. This Rador drew aside cautiously, beckoned us and we stepped through. It appeared to be a tunnel cut through soft green mould. Its base was a flat strip of pathway a yard wide from which the walls curved out in perfect cylindrical form, smoothed and evened with utmost nicety. Thirty feet wide they were at their widest, then drew toward each other with no break in their symmetry; they did not close. Above was, roughly, a ten-foot rift, ragged edged, through which poured light like that in the heart of pale amber, a buttercup light shot through with curiously evanescent bronze shadows. "Quick!" commanded Rador, uneasily, and set off at a sharp pace. Now, my eyes accustomed to the strange light, I saw that the tunnel's walls were of moss. In them I could trace fringe leaf and curly leaf, pressings of enormous bladder caps (Physcomitrium), immense splashes of what seemed to be the scarlet-crested Cladonia, traceries of huge moss veils, crushings of teeth (peristome) gigantic; spore cases brown and white, saffron and ivory, hot vermilions and cerulean blues, pressed into an astounding mosaic by some titanic force. "Hurry!" It was Rador calling. I had lagged behind. He quickened the pace to a half-run; we were climbing; panting. The amber light grew stronger; the rift above us wider. The tunnel curved; on the left a narrow cleft appeared. The green dwarf leaped toward it, thrust us within, pushed us ahead of him up a steep rocky fissure--well-nigh, indeed, a chimney. Up and up this we scrambled until my lungs were bursting and I thought I could climb no more. The crevice ended; we crawled out and sank, even Rador, upon a little leaf-carpeted clearing circled by lacy tree ferns. Gasping, legs aching, we lay prone, relaxed, drawing back strength and breath. Rador was first to rise. Thrice he bent low as in homage, then--