That's partly because the sketches are a puzzle too.

Hidden in many of the drawings is the name of Hirschfeld's daughter Nina, who now lives in Austin. The number next to his signature indicates how many Ninas are worked into the cross-hatching ad scrolly curlicues out of which he fashions his striking likenesses of stars of stage, screen, music, television and politics.

The irresistable game of hide-and-seek began in 1945, when Hirschfeld celebrated the birth of his only child by working a poster for Nina the Wonder Child into the background of a sketch of the musical 'Are You With It?' Inspired by parental pride, the prank soon grew into a national institution, and the Pentagon once tested pilots' visual quickness by flashing his drawings on a screen and timing their ability to spot the Ninas.

The St. Louis-born Hirschfeld, who turns 86 in June, began his career by studying sculpture and painting in New York and Paris. (Too poor to afford anything but cold-water flats, he grew his famed Santa Claus-style beard because he lacked water hot enough for shaving.)

But he eventually decided that a sculpture "is just a three-dimensional drawing, a drawing you trip over in the dark." Smitten with the elegantly pared-down work of Hokusai and other masters of pen and ink that he encountered during residence in the Far East, Hirschfeld "latched on to line, pure line."

That shift in medium and style was fortuitous, since it allowed him to forge a more than 65-year association with newspapers.

"One of the limitations in the publishing business, particularly in newspapers," is that your drawings "are printed on a kind of rough toilet paper that, if you do anything but pure line, you're looking for trouble."

Hirschfeld, whose first published drawings appeared in the New York World in 1923, became a theatrical caricaturist quite by accident. "It was never a deliberate thing on my part. Like everything in my life, it's been accidental and foolish." Show biz just "lent itself to my type of foolishness."

In 1925, while watching a performance by Sacha Guitry and Yvonne Printemps, he began doodling in his program. His companion, ace press agent Richard Maney, liked his drawing of Guitry and sold it to the now-defunct Herald Tribune.

Soon supplying theater drawings for a number of New York's then-abundant dailies, Hirschfeld was eventually "hired" by The New York Times in 1929 in a handshake arrangement that has never had to be formalized, and the prolific penman calculates he has created well over 3,000 drawings for the Times alone.

The indefatigable Hirschfeld works seven days a week in a studio on the top floor of the Upper East Side town house he and his wife since 1943, former German stage star Dolly Haas, bought in 1947. Sitting in the same barber chair he has used for five decades, he plies his trade on 20-by-30-inch paper because "you can have more freedom on a large drawing."

Recently commissioned by the U.S. Postal Seervice to create commemerative stamps of Laurel and Hardy, silent screen star Mary Pickford and opera great Rosa Ponselle, he leaves analysis of his work to others. (New York Times art critic John Russell wrote the introduction to the most recent collection of Hirschfeld drawings.) His only explaination of his creative method is, "I invent a problem that never existed before and solve it. I take a blank piece of paper and insist upon creating a problem."

Some of Hirschfeld's drawings are dizzingly ornate, but "the simple ones take the longest. It's easy to embroider. You keep adding another little gimmick. It just goes on and on when you don't know what you're doing."

The hard work is "when you're really concentrating and trying to eliminate" and whittle a sketch down to the essentials. An exaggerated style is fine for caricaturists like David Levine, Hirschfeld allowed. "I just don't find making a big nose bigger very witty. I did a drawing of Jimmy Durante many years ago and i left the nose out, which served the same purpose: draw attention to the nose."

Hirschfeld and his wife go to the theater about three nights a week. "Other nights we sit around the house and have people in and solve the world's problems. I give my advice," he chuckled, "whether they seek it or not."

Hirschfeld has been likened to artists such as Beardsley, Daumier, Beerbohm and even Hans Holbein the Younger. His drawings have been collected by prestigous institutions such as the Metropolitan, Fogg, Whitney, and Museum of Modern Art. Margo Feiden Galleries, his agent since the 1960s, has been retailing his drawings almost as quickly as he can turn them out. (price tags range from as little as $10 for an unsigned poster or $350 for recent limited-edition lithographs and etchings up to $1,500-$15,000 for original drawings and four figures for a portrait.) He has a theater named after him in Miami Beach. And a jigsaw puzzle featuring caricatures of 15 famous actors has just been issued.

The New York theater's official portrait painter, Hirschfeld strayed onto the other side of the footlights only once. In 1947 he collaberated with his friends S. J. Perelman, Ogden Nash, and Vernon Duke on a musical, 'The Sweet Bye and Bye.' Promply folded in Philadelphia, it was such a colossal turkey that "Perelman and I had to leave the country. That's how we happened to go around the world" by tramp steamer and hilariously chronicle their misbegotten trek in the classic 'Westward Ha!' "By the time we came back nine months later, all was forgiven."

Hirschfeld has no proteges, "but I get quite a lot of fan mail from young artists. I do my best to discourage them," he confessed. "I always point out to them it's no way to make a living.

"If you want to make money, " Hirschfeld advises aspiring Hirschfelds, "open a delicatessen."