As they emerged from the gulley and came to the place where Mick had slashed down the budded stalk with his ray gun, Ghor halted. The shriveled burned bud lay on the ground, but the stalk had disappeared. The earphones in Mick's spacesuit caught Ghor's startled gasp: "Ngye!" "It attacked us yesterday after we jumped out of the corn patch," Alf was explaining. "Mick knocked it over with his ray gun." "It is the first one that has ventured on this side of the planet in several years," Ghor explained. "It's one of the mobile plants I was speaking of. You see, the stem has regenerated a new bud and has moved on." "We saw several of them--" "Several!" Ghor seemed to stiffen. "Gentlemen. It is not safe here. We must go back to my cabin. The Ngye is one plant that is deadly." "I thought your father made trees out of them," Mick said. "At first they were docile. My father developed many kinds of plants from them and I myself created the corn from hybrid Ngye plants, but the process of survival played a curious prank by developing in the untouched plants a sense of hatred for these new variations, as well as an everlasting enmity for my father and myself. It was as if these plants resented being made over into alien forms. My father developed a poisonous substance which he spread on the soil which drove the Ngye plants to the other side of the planet. Apparently they have come back. It means, my friends, that mankind must go to war to save himself and his products." Ghor already was walking rapidly back toward the gully. "Couldn't you make some other poison to get rid of them again?" Alf asked. "I might, but it would take time. And--" Ghor seemed to choke, "--it was the poison that killed my father." As Ghor reached the first turn in the gulley, he halted and then sprang back. A gleaming spark landed at his feet and heated the rock to incandescense. "Trapped!" he groaned. "There's a forest of Ngyes in the path ahead of us." Mick pushed forward, his ray gun in hand. He caught a glimpse of a forest of leafless stems, surmounted by ugly, bulging bulbs. Ghor tugged Mick back, just as a shower of sparks shot from the stalks. "How do they know where we are?" Mick asked. "Doesn't our degaussing equipment work?" "The Ngye has more sensitive perception than most plants. You forget the radio waves from our phones. The plants are able to find us by those." "Maybe we can rush them," Mick suggested. "Alf and I can use our ray guns to burn a path through to the cabin--" Ghor shook his head. "No. Before we seared half of them, the rest would have melted us into grease. Besides, fire won't work with them. It will only multiply our enemies." A warning cry came from Alf. "They're behind us, too!" Mick glanced down the gulley. A moving forest was circling the bend. The Ngyes seemed to progress with an amoebic motion, as if their roots tugged them along over the loosely packed soil. "Quick, Alf! Take Ghor's arm. We can jump for it!"