To toss or not to toss: Allegra Kent remembers a hairdo disaster onstage.

The Cage, created by Jerome Robbins in 1951 to music by Stravinsky, uses stylized choreography to investigate an insect society, somewhat like that of preying mantises or black widow spiders, in which the female finds the male's existence superfluous after mating and kills him without compunction.

For the lead role of the Novice, Robbins envisioned a black wet-looking wig. Nora Kaye's freshly showered hair was the original inspiration for this look. Perhaps Robbins, a keen observer of flora and fauna, noticed that Kaye's head uncannily resembled a pupa--in insect life the tender stage between the larva and the imago. In contrast, the hairstyle for the corps girls was to be a disheveled mop, arranged ad hoc.

A long time ago--perhaps in the late 1960s--while I was performing the Novice with New York City Ballet at the New York State Theater, I had a hair-do disaster of alarming magnitude. Mid-ballet while I was whirling, twirling, and executing the ferocious movements that would eventually kill the first boy bug in my life, I felt two bobby pins slip from their place, slither down my neck, and fall to the floor. An excess of hair gel and centrifugal force were at the root of the problem. As more and more of the foundation around the wigband became unhinged, and I continued with the head-snapping, foot-stomping choreography, I realized my wig was leaving me. It was half on and half off, hanging down near my ear. This in-between state was intolerable, so, in a panic, I ripped it off and tossed it into the wings--but not the one where Mr. Balanchine stood calmly observing my performance. Yes, Mr.B was watching this particular Cage from his favorite offstage viewing position downstage right. I felt humiliated, anticipating his negative response to my unexpected hair change. Would he ever take me seriously again, or would he regard me as merely a prankster? Yet there was no time to think of my liberated locks. The only thing I could do was plunge into my part with more intensity.

After the final bows, I hoped to avoid Mr.B, but he started walking towards me. At that moment I despised myself, as I started to imagine what he might say: "That was awful dear. You ruined the ballet."

I steeled myself for an upbraiding of supreme vehemence. I had been dancing professionally for over 15 years and arranging my own hair since day one. I had no excuse.

But then I saw that Mr.B was smiling. "That was wonderful," he said in an enthusiastic tone. "You should lose the wig in every performance."

I was astonished. He had judged the moment with an unprejudiced eye and seen a buggy metamorphosis that turned a sleek little creature with a neat Napoleonic bob into a Jacquelina-the-Ripper with straggly strands.

"Oh, I thought you'd be really upset with me."

"No. That was a good performance."

What a gracious guy! By some miracle, Mr.B was making me feel better rather than worse. He had chosen to be a contrarian. But I was glad Jerry Robbins wasn't present. After all, The Cage was his ballet.

Some notes on the subject of hair:

* Hairstyles often give clues to the emotional undertones of a ballet. Unruly emotions and unruly hair go hand-in-hand.

* Hairpin loss on stage (a quick change from neat classical to tumbling tresses) can mean madness, as in Giselle, or overwhelming despondency, as in Serenade.

* There are also heroines who arrive on stage without any hairpins at all (the hair is down). If she is holding a candle, she may have a sleeping disorder and possess extrasensory perception, like the woman in white in La Sonnambula (notice that she always exits backwards). If the heroine has her hair down, is wearing black underwear, and leaves the stage by diving through aluminum foil, it may mean that she has unruly emotions and a touch of self-destructive madness (but not a sleeping disorder) like the silent Anna in The Seven Deadly Sins.

* Conclusion: Exciting exits are arresting, but the audience is happier when wigs and crowns don't fall off, wisps stay in place, and the ballerina doesn't tear her hair out during the bows. Dancers who receive criticism and corrections from their artistic director right after a performance know that these immediate reflections are of great importance. Therefore, high into the clouds I toss a thank you to Mr.B, because he was so kind to me on that night of long ago when I was extremely vulnerable and ready to tear my own hair out.

Allegra Kent, a former principal at New York City Ballet, is on the faculty of Barnard College and a guest artist at Princeton University. She is the author of Allegra Kent's Water Beauty Book (out of print) and an autobiography, Once a Dancer.