Agnes de Mille, self-conscious maverick and theatrical sorceress and withal one of the most distinguished dance artists this country has ever produced, loves to get off lines like the following, in this case about Isadora Duncan: "Her bare feet caused more ruckus in those days than bare genitals today." It's a sample of the lightly salted epigrams she comes up with on the PBS special, "Conversations About the Dance," taped live at Los Angeles' Greek Theatre and airing tonight at 9 on Channel 26.

The 90-minute show is an informal trek through dance history with an emphasis on the United States, written and narrated by de Mille, and illustrated by dancers of the Joffrey Ballet and several guest artists.

At one point de Mille notes that a prime rule Broadway choreographers learn is "Don't be a bore." In her effort to follow this precept, however, she tends to play somewhat fast and loose with historical reality. The result, then, is a highly personal memoir on a favorite subject by one of its notable practitioners.

Even in these terms, though, both the narrative and the illustrative material seem disappointingly thin. There are two smashing high points among the performances. One is hoofer Honi Coles, one of the surviving grandmasters of jazz top dance giving a charming impression of Bill Robinson and a fleet solo of his own; the other is the "riding" sequence from de Mille's supreb "Rodeo," robustly done by a Joffrey contingent.

Elsewhere what we get is a series of catchily worded but seriously debatable generalizations, some dubious and feebly performed reconstructions (Elssler's "Cachucha" and Duncan's "three Graces," for example), and anomalous omissions. A TV program is hardly the place for rigorous or comprehensive scholarship, and de Mille does manage to pay tribute to such giants as Fokine, Balanchine, Tudor, Robbins and Graham (though none comes in for illustration). But the only even remotely contemporary choreographer cited is Bella Lewitzky -- a respected but scarcely central figure -- and its hard to reconcile de Mille's mention of Gower Champion or Bob Fosse with the absence of reference to the likes of Ted Shawn, Charles Weidman, Merce Cunningham, Paul Taylor and others of their importance. "Conversations" is entertaining and has an inimitable de Mille tang, but it's an uneven affair by any accounting.