"Heredity and environment," Jack parroted like a freshman. Kesserich nodded. "Suppose--this is just speculation--that we could control heredity and environment. Then we could re-create the same individual at will." Jack felt a shiver go through him. "To get exactly the same pattern of hereditary traits. That'd be far beyond us." "What about identical twins?" Kesserich pointed out. "And then there's parthenogenesis to be considered. One might produce a duplicate of the mother without the intervention of the male." Although his voice had grown more idly speculative, Kesserich seemed to Jack to be smiling secretly. "There are many examples in the lower animal forms, to say nothing of the technique by which Loeb caused a sea urchin to reproduce with no more stimulus than a salt solution." Jack felt the hair rising on his neck. "Even then you wouldn't get exactly the same pattern of hereditary traits." "Not if the parent were of very pure stock? Not if there were some special technique for selecting ova that would reproduce all the mother's traits?" "But environment would change things," Jack objected. "The duplicate would be bound to develop differently." "Is environment so important? Newman tells about a pair of identical twins separated from birth, unaware of each other's existence. They met by accident when they were twenty-one. Each was a telephone repairman. Each had a wife the same age. Each had a baby son. And each had a fox terrier called 'Trixie.' That's without trying to make environments similar. But suppose you did try. Suppose you saw to it that each of them had exactly the same experiences at the same times...." For a moment it seemed to Jack that the room was dimming and wavering, becoming a dark pool in which the only motionless thing was Kesserich's sphinx-like face. "Well, we've escaped quite far enough from Jamieson's marine worms," the biologist said, all brisk again. He said it as if Jack were the one who had led the conversation down wild and unprofitable channels. "Let's get on to your project. I want to talk it over now, because I won't have any time for it tomorrow." Jack looked at him blankly. "Tomorrow I must attend to a very important matter," the biologist explained. IV Morning sunlight brightened the colors of the wax flowers under glass on the high bureau that always seemed to emit the faint odor of old hair combings. Jack pulled back the diamond-patterned quilt and blinked the sleep from his eyes. He expected his mind to be busy wondering about Kesserich and his wife--things said and half said last night--but found instead that his thoughts swung instantly to Mary Alice Pope, as if to a farthest island in a world of people. Downstairs, the house was empty. After a long look at the cabinet--he felt behind it, but the key was gone--he hurried down to the waterfront. He stopped only for a bowl of chowder and, as an afterthought, to buy half a dozen newspapers.