For almost all the dances performed by the Washington Ballet at Wolf Trap Barns last night, the small stage was visibly constricting and unsuitable. The exception was a premiere by Washington School of the Ballet faculty member Sally Trammell, "Rubrum Phrases," whose delicacy and gestural subtleties can probably only truly be appreciated in a chamber setting.

"Rubrum Phrases" -- the title is a botanical term for lily -- is set to Bach's orchestral Suite No. 2 with sections arranged out of sequence. The work employs the conventions of court dance as a foil for quirks and jazzy swayings that occasionally burst through the decorous veneer of pretty posings and courtesies. There are wonderfully witty moments -- John Goding's diagonal line of jerks and twitches in "Polonaise and Air," which seem the movement equivalent of speaking in tongues, and Lael Evans' fluttering falls out of arabesque in the "Menuet" -- but for the most part, the work lacks the sustained thread of a play upon conventions. One also waits in vain for that moment of risk or zaniness which will define the dance. Ultimately, it becomes an overextended one-liner.

The best of the choreography is reserved for the men, whose gestures are more mannered and sharply defined than the sweet promenadings of the women. This inequality is highlighted when the women, in the final "Overture" movement, inexplicably gambol with lily-pink cloths. The scarves obviously quote from the Doris Humphrey/Ruth St. Denis early modern dance classic, "Soaring," and there are in fact many other quotations or references or borrowings from other modern dance choreographers, including Paul Taylor, Martha Graham and Lar Lubovitch.

Other highlights of the program were the Washington-area debut of a much-awaited partnership and a welcome revival. The partnership of Robert Wallace, a dynamic young technician, and Katita Waldo, a rising young apprentice who is being carefully nurtured within the company, proved something of an odd match in the Bluebird pas de deux from "The Sleeping Beauty."

Wallace indeed filled the role with conviction and aplomb (though only half of the male variation was presented). His stocky straightforwardness put him at odds, however, with the extremely elongated Waldo, whose soaring extensions and beautifully arched feet hold the promise of mature elegance. For the present, however, the Bluebird proved to be too much for her -- both technically and artistically. Those beautiful extensions cover a weakness in jumps and a general lack of strength in the back and feet; her expressiveness was erratic.

Eric Hampton's "Slow Movement," seen for the first time since its 1979 premiere season, is a graceful readdition to the Washington Ballet's repertory, both for the smallness of its scale and the emotionalism of its subject. As rendered last night by Janet Shibata and William Batcheler, "Slow Movement" (set to Webern's "Slow Movement for String Quartet") is thoroughly enigmatic. There is a struggle -- possibly to the death -- in a couple's relationship. But why, or on what terms, or what it is about, is left to the viewer. It is the mystery of this quietly intense work that is the basis of its appeal.

The Wolf Trap program, which will be repeated tonight and tomorrow, also included repertory staples, "Momentum," "Albinoni Adagio" and "A Night at the Ballet."