KENT PATTERSON THE WEREYAM WHEN THE CLOYING ODOR of scorched marshmallow and hot yam filled the greenhouse, Bill Mauer cursed softly. Another damned premature. He got up from his watchman's cot. The light of the full moon gleamed on the glass walls, throwing ghostly shadows over a jungle of yam vines as high as his head. He could see nothing, but the smell of hot candied yam grew stronger by the second. Sighing, Bill picked up his auto-rooter. Nothing to do but find the premature and dig it out before the yam burst and let the bad strain of nanocritters contaminate the whole patch. Bioengineered self-cooking yams had made his fortune. Self-cookers let even the busiest houseperson serve his/her family with nutritious meals with all of the rich goodness of genuine home cooking. But somehow the new, improved yams with the automatic self-candying option just weren't working out. He should have known better than to buy his yam nanotechnology from a firm calling itself "WerTech Transformations." As Bill walked down the shadowy corridor sniffing out the premature, yam plants rustled in the wind, their dry leaves scratching against the glass walls. Now a yam runner caught around Bill's ankle, and he bent over to unwrap it. Wait a minute. There was no wind inside the greenhouse. Spooked, Bill ripped the yam loose, but a dozen others gripped his other ankle. He kicked viciously, but more and more vines clutched at his arms and legs. He tried to scream, but a burning hot candied yam thrust through his lips, cramming itself into his mouth and choking off the air. A sharp yam stem plunged into his jugular, and a hot wave of pain struck as tiny nanocritters surged through his arteries, multiplying in their millions, transforming every protein, every molecule of his body. His arms and legs withered away, and his torso grew large, globular, yam shaped. And now Bill, for the first time in his life, understood yams. He understood the softness of the mothering soil. He understood sunshine, the feel of rain, gentle as butterfly's wings, upon yam leaves. But most of all, he understood yam pain, the brutal heat of an oven, the steel of a knife slashing through the skin. Now he understood forks. He understood cruel white teeth tearing at the tender yellow flesh, and all the degrading vocabulary of man's inhumanity to yams. Rage flowed through his body, white, screaming anger. He felt a thirst for vengeance which must be satisfied, and could only be satisfied with blood, enough blood to drown centuries of oppression, millennia of baked yams, boiled yams, yams on the side, yams with butter, yams with sour cream, and worse, yes, worse than all of those -- candied yams. Now the light of the full moon gleamed on the glass walls of the greenhouse. Bill's transformation was complete. Like a huge round moon he rolled to the greenhouse door, and a great rough beast, its hour come round at last, slouches toward the grocery stores to be born.