David Cavagnaro tells--and color photos show--how he, his wife Maggie, and small son Pippin planted seeds in the spring and then when the crop was ready gave a party where everyone carved jack-o'-lanterns, lit them with candles, and sent them adrift in a nearby (California) lagoon on home-made wooden ""boats."" Next morning the washed-up pumpkins were gathered and put on the compost heap, where their faces aged and withered but ""one day. . . a wonderful thing happened. . . . From the eye of one contented and happy old sage, a seed had sprouted."" Whether he's reflecting on the lit-up carvings (""Lined up in front of us were congressmen, actors, generals, workers, and poets. . . . We looked at the squash people and saw ourselves"") or evoking the feeling that ""came out of fond childhood memories of family gatherings and from deep instincts of tribal festivities in which our ancestors gave thanks for a good harvest""--Cavagnaro doesn't really gear this to a child's sensibility. But the jack-o'-lanterns are a sight-amusing in daylight, spooky when lit--and this very individual demonstration of life- and-death cycles might catch certain receptive children in its spell.