While rummaging through a dusty attic at the Smithsonian Institute in Washington, D.C., Kjell Sandved found an old cigar box that set him on a 20-year quest.

In the fragrant Havana box was a collection of rare butterflies and moths. Sandved, who left his publishing business in his native Norway to work as a Smithsonian volunteer in 1960, was captivated by the wing markings of a particular little Sphinx moth.

“It had very stylish wings, swept back like the wings of a fighter jet,” Sandved said recently from Washington. “When I put it under a microscope, and looked at the markings on the scales, I found a perfect, tiny letter F.”

Sandved photographed the image, hung the picture on the wall of his office, and forgot about his discovery.

“It took my wooden, Scandanavian head a year or more before I thought, `My gosh, maybe there are other letters to be found in the markings of butterflies and moths.’ ”

There were many more letters to be found — an entire stylized alphabet, to be exact — along with the numbers 0 through 9. Capturing each of them on film required a journey of two decades through the swamps and jungles of more than 25 countries.

The result is Sandved’s “Butterfly Alphabet,” which has become the best-selling nature poster in the world since its publication a little more than a year ago. For Sandved, who teaches nature photography for the Smithsonian and lectures and makes films on animal behavior, the alphabet hunt offered him a loving glimpse into a universe of small wonders that most people overlook.

“Most of the letters were found in places such as Brazil, Peru, and Panama,” said the amiable naturalist. “I also found letters in Africa, New Guinea, Sumatra, and Malaysia. If I had known Greek or Chinese, I could have found all sorts of different letters in those languages.”

Each butterfly or moth wing is made of millions of overlapping microscopic scales. Some of the scales contain pigment, he said, while others are grooved to capture and reflect light to produce irridescent blues, greens, and metallic effects.

“No butterfly is marked exactly the same as another,” he said. “I think all of the design elements man can think of have already been painted by nature’s own hand on the wings of butterflies and moths.”

Equipped with a customized camera and sophisticated close-up lens, Sandved stalked his wing-borne alphabet early in the morning and late at night.

“The butterflies and moths are sluggish at those times, so I could get up close,” said Sandved, who began his search while vacationing in tropical settings around the world.

Of all 26 letters, he said, the most difficult to find were the asymmetrical “G” and “R.” He eventually found “Gs” in Brazil and Africa, and an “R” in Malaysia.

The easiest letter of all was the “O,” an abundantly occuring camouflage design in nature.

“The most compelling design in the world is the eye,” he said, “which appears on a butterfly wing as an `O.’ The eyes can startle an enemy with a flash of a wing or invite a bite while deflecting an attack to the more vulnerable body.”

While gathering many hundreds of thousands of images for the poster and his seven nature books, Sandved has not always been delighted with nature’s talent for surprise. He has encountered venomous snakes while photographing tropical orchids, and once returned from a mountain trek in Borneo with a back full of leeches.

Yet the most terrible surprises of all have been manmade.

“The most awful aspect of travel has been returning to those places I photographed 20 years ago and see them clear-cut,” he said. “I have to think that some of the butterflies I photographed might now be extinct.”

With his Butterfly Alphabet, Sandved hopes to remind people everywhere of nature’s fragile beauty.

“I get all kinds of letters from kids who have become so interested in these little discoveries,” Sandved said. “Maybe by looking closely at things in nature they can help protect what they see.”

For copies of the Butterfly Alphabet poster, write Kjell B. Sandved, P.O. Box 39138, Washington, D.C. 20016, or call