Gene Wolfe's "In Green's Jungles" is the second volume, after "On Blue's Waters," of his ambitious SF trilogy, "The Book of the Short Sun." It is again narrated by Horn, who has embarked on a quest from his home on the planet Blue in search of the heroic leader Patera Silk. Now Horn's identity has become ambiguous, a complex question embedded in the story, whose telling is itself complex, shifting from place to place, present to past. Horn recalls visiting the Whorl, the enormous spacecraft in orbit that brought the settlers from Urth, and going thence to the planet Green, home of the blood-drinking alien inhumi. There, he led a band of mercenary soldiers, answered to the name of Rajan, and later became the ruler of a city state. He has also encountered the mysterious aliens, the Neighbors, who once inhabited both Blue and Green. He remembers a visit to Nessus, on Urth. At some point, he died. His personality now seemingly inhabits a different body, so that even his sons do not recognize him. And people mistake him for Silk, to whom he now bears a remarkable resemblance. "In Green's Jungles" is Wolfe's major new fiction, "The Book of the Short Sun," building toward a strange and seductive climax.