Years ago I learned to sail by the wind on a 26-foot sloop in San Francisco Bay. After the initial terror, I came to relish the exhilaration of skimming across the water, rocketed by gusts and tugged by currents. At times I’d imagine endlessly drifting on the open sea with the sun and the stars as my only companions.

Velella velella (from the Latin for “veil”), commonly known as “by-the-wind sailors,”  live this fantasy. Ancient mariners found in oceans around the world, they have no need for seaworthy vessels. They are shaped like exquisite toy sailboats.