Carmen McRae is scared.

"I don't hear anybody young doing what I do or what Sass does or what Fitz does or even what Betty Carter does."

Sass is Sarah Vaughan and Fitz is Ella Fitzgerald. With McRae, they are the classy triptych of America's jazz singers; they are also 59 and 65 respectively, encircling McRae's 61 years.

"I have tried to figure it out and I can't," McRae says, sitting on the edge of a straight-back chair in her tiny dressing room at Blues Alley, where she is appearing through Sunday. "I have no idea why there are no young jazz singers . . . I can't say there's one that I know of in their twenties or thirties who is going to come along and sit in when we all . . . leave. We're becoming an endangered species and it's really very frightening. I can't go on for ever and ever."

A steady stream of fans stops at the dressing room door for autographs or handshakes or to acknowledge McRae as an inspiration. Some will tell her they are jazz singers, too, that they've gone that difficult course because of her. But what Carmen McRae hears from them are simply words. She does not hear the songs, she does not sense the insistent pulse, the passion that raced through her as a 13-year-old New Yorker inspired by another legendary jazz singer, Billie Holiday.

"I adored her before I ever met her," McRae says of Lady Day, whose incendiary nuances she carried forward in her own distinctive fashion. As Holiday did, McRae lives a lyric. She inhales it and breathes it back downright personal. It's an attitude absorbed in the mid-'30s.

"Lady wasn't that much older than I was at the time, maybe three or four years. I first heard her records, then saw her at Apollo. When I saw her, I didn't believe it. She was like something from another planet. She was hip. And in those days, when we said hip, that was the epitome of everything."

McRae didn't know Holiday personally then. She also didn't know if she wanted to sing.

"I used to sing for my friends and play the piano, and every day I was writing songs that were so terrible. When I went to see Lady, there were two things in my head: either I would never sing, because of what she did to me emotionally, or I would sing good. That was it."

In the late '30s, McRae became friends with Irene Wilson, who had been married to Teddy Wilson, Holiday's accompanist and arranger.

"She was suicidal, coming out of a dismal marriage , and I think I unknowingly saved her life. I was all of 17 years old, but I somehow gave her the inspiration to write things like 'Some Other Spring' and 'I'm Pulling Through.' And so she introduced me to Billie, and I used to sing these songs for her. All the songs of Irene's that Lady recorded she heard from my mouth first."

Holiday's brilliant talent would become diluted by alcohol and drug abuse, and McRae knew that side of her as well. "She used to take me out with her. Inevitably, I'd have to leave her because she had the strongest constitution of anybody. We'd smoke pot and in those days all the pot was good. And she used to drink rum and Coca-Cola. I don't remember what I was drinking but whatever it was, halfway through the night I would be so stoned and out of it I'd have to leave and go home."

McRae never fell hard like her idol, who she says is "still my greatest inspiration. There are times that I will sing a song of hers and I will throw in something, sometimes just a note, that I remember her doing. But today that's as far as it goes because today I think I have come into my own."

After a "brief minute" as a chorus girl in Atlantic City, McRae found herself stranded in Chicago ("I went there with someone who wanted to take care of me . . . which he didn't do," she says tartly, apparently still miffed 40 years later). She landed a job in a bar whose owner would bring out a bottle at slow times for an unhappy hour. "A few of the girls would sit around the piano; we used to call it the torch hour 'cause we'd sing nothing but breaking-your-heart tunes. The girls loved that."

She eventually landed a solo job on a two-week trial that turned into a 3 1/2-year stay.

"Then there was no looking back," she says. "I was so happy to know I could make a living playing and singing. Then I said, 'Hell, if I can do this in Chicago, I can do this in New York.' "

She went back and in 1954 a producer asked her if she'd like to make a record. She answered, "You're damn right I would!"

Although McRae has made the occasional pop concessions demanded of all jazz singers, she has always stayed true to her jazz experience, interpreting songs with a unique warmth and communicative skill, elevating the prosaic, illuminating the passionate, advancing the lyrics past entertainment into confession. She also never stopped working. She says the last two years have been the best of her career.

"I can't make some of the high notes I used to," she concedes, "but by the same token, back then I couldn't make the low notes I'm making now."

She leans forward, offering the wisdom of a Jimmie Lunceford lyric that's as much a jazz aphorism as Duke Ellington's "it don't mean a thing if it ain't got that swing."

Carmen McRae, who knows, snaps her fingers and swings the lyric softly, "It's not what you do, it's the way how you do it. That's what gets you results."