Expanding one of his splendid short stories (a standout in The Year's Best Science Fiction, 1984), Bear has fashioned a woefully ragged and aimless novel--despite some arresting ideas and images. Genius researcher Vergil Ulam, developing organic microcomputers, hits upon the notion of putting the cell's own DNA to work as a computer; his technique is so successful that computing bacteria become as intelligent as mice. But then Vergil's self-serving boss orders his research shut down--so, to save the experiment, Vergil injects himself with his own computerized blood cells. The cells spread; soon his body's other cells, working in concert, become more intelligent than Vergil himself--beginning to redirect his metabolism to their own ends. And meanwhile Vergil unwittingly infects others with the computing cells, causing them to undergo weird physical transformations and eventually dissolve. . . as they become linked in a vividly described super-organism encompassing plants, animals, even buildings. Unfortunately, however, while some of the original story's concepts remain striking, Bear's additions--uninvolving subplots, vague and unsatisfying explanations--only manage to dilute and obscure. Very disappointing work from a strong talent.