Only a few scientists worried about what would happen if the margenes should disappear as suddenly as they had arrived. Attempts at breeding the creatures had failed completely. They did not undergo fission, they did not sporulate, they seemed to have no sex. No methods of reproduction known in the plant or animal kingdom seemed to apply to them. Hundreds of them were kept alive for long periods--they lived with equal ease in either air or water, and they did not take nourishment, unless they absorbed it from their environment--but no sign of fertility ever appeared. Neither did they seem to die of natural causes. They just kept coming in.... On the night of May 7, 1969, not a single margene was visible in the ocean or on the beach. They never came again. What happened as a result is known to every student of history. The world-wide economic collapse, followed by the fall of the most stable governments, the huge riots that arose from the frantic attempts to get possession of the existing stocks of margene cakes or of the rare luxury items of other edibles, the announcement by the U.S.S.R. that it had known from the beginning the whole thing was a gigantic American hoax in the interests of the imperialistic bloodsuckers, the simultaneous atomic attacks by east and west, the Short War of 1970 that ruined most of what bombs had spared of the Earth, the slow struggle back of the remnant of civilization which is all of existence you and I have ever known--all these were a direct outgrowth of that first appearance of the margenes on the beach near San Diego on an April night in 1960. Marge and Gene Towanda were divorced soon after they had both lost their jobs. She was killed in the hydrogen blast that wiped out San Diego; he fell in the War of 1970. "Margene" became a dirty word in every language on Earth. What small amount of money and ability can be spared is, as everyone knows, devoted today to a desperate international effort to reach and colonize another habitable planet of the Solar System, if such there be. * * * * * As for the margenes, themselves, out of the untold millions that had come, only a few thousand were lucky enough to survive and find their way back to their overcrowded starting-point. In their strange way of communication--as incomprehensible to us as would be their means of nourishment and reproduction, or their constitution itself--they made known to their kin what had happened to them. There is no possibility, in spite of the terrific over-population of their original home and of the others to which they are constantly migrating, that they will ever come here again.