Of all the strong critics who write regularly for The New Yorker--Porter on music, Updike on books, Kael on film (sometimes)--Croce is perhaps now the strongest. Unlike Porter, she never lets her high standards and vast learning slide into donnish fingerwagging. Unlike Kael, she never lets her passion turn into a gush. And unlike Updike, she has the time and focus to maintain a steady dialogue with the most important work in her field. In this second collection, then, covering seasons from '77 to '81, Croce's searching intellect and sterling prose (sharp-edged yet warm-blooded) are trained on nearly every major dance artist and issue--in dozens of medium-length essay-reviews. Balanchine, of course, remains the prime subject: there's an exhaustive 50th-year look at Apollo, plus notes on the ups-and-downs of other pieces; there's a keen eye on the City Ballet roster (""Ballade is evidence that Balanchine is unwilling to let Merrill Ashley carry on as if she were an uninteresting woman""); each new GB work is greeted with awe, love, and suspicion. But, having put her basic Balanchine case on record in Afterimages (1977), Croce now more freely turns to the rest. Tharp has faded into ""strained kitsch,"" perhaps; but there's fresh interest in Merce Cunningham and Paul Taylor (like Fokine, he ""looks too simple to be as impressive and hypnotic as he is""), in ""Mysterians,"" like Meredith Monk or Lucinda Childs. There are trips to London for the Royal (""sinking into a cozy provincialism""), to Brooklyn for the San Francisco--keeping shrewd track of Michael Smuin's talent. Traditions--Bournonville, Petipa, Graham--are analyzed, monitored, nothing taken for granted. Performances are finely cross-referenced--from Swan Lake at Dance Theatre of Harlem (""the stresses that black dancers lay on classical style end by bleaching it, but it comes out pure rather than white"") to Fancy Free at the City. (""When the sailors tease the girl. . . the action that at Ballet Theatre can look ad lib is so precisely set and executed that it becomes harsh: these boys might be muggers."") And, as always, Croce is unusually receptive to side-genres (mime, ice-dancing, acrobatics), unusually acute on other media: she nails The Turning Point; she laments the state of ballet records, of ballet history (""We must stop hoarding and start sifting the ruins""); she's superb on music for dance, whether it's Mahler (""the composer most often employed to dye a choreographer's musings the shade of concert-hall brown that lets us know Significance is in the air"") or Randy Newman (""horsehair on the outside, cretonne on the inside""). No doubt about it: a breathtakingly fine critic in full regalia--enriching the dance for fellow enthusiasts, snaring others in with her serious, vivid mind-play.