This "novel" brings together a decade's worth of stories about Haviland Tuf, an honest but thoroughly small-time interstellar trader who happens to acquire a centuries-old and miles-long seed-ship of the once powerful Earth Ecological Corps. Originally a deadly weapon, it alone preserves the secrets of a now-forgotten science and still functions well enough to create, gene-splice and clone any of a myriad species of plant and animal, both benevolent and destructive. The eccentric but ethical Tuf now styles himself an ecological engineer and wields his ship's treasures to solve the problems plaguing farflung settlements, from famine to sea serpents. These colorful tales mostly skirt the more interesting and prickly issue of Tuf's playing god to fundamentally change the cultures he encounters. Still, the seed-ship is a wonderful idea and Tuf, protecting his pet cats from the charge they are useless "vermin," is a droll hero.