Mark Morris's choreography can make familiar music sound brand-new. In the Mark Morris Dance Group's concert of company favorites at Wolf Trap on Tuesday, he ferreted out the deep layers of Lou Harrison's Grand Duo for Violin and Piano and Serenade for Guitar.

The evening's lack of premieres and some tired dancers in the final piece did not make for an incredibly exciting evening, but musical insight, well-crafted choreography and generally excellent dancing made it worthwhile.

Music has always been central to Morris's creative process. He formed a music ensemble in 1996 to ensure that the company always performs to live music, and he has relied almost solely on the classical canon while other choreographers, in ballet and modern, have often looked to rock music.

"Grand Duo," a 1993 ensemble work, pulls much from Harrison's opening trembling piano, giving the dancers' unison movement a percussive sharpness. The work has a frenzied air as dancers move in every direction, but repeated motifs calm the visual chaos.

The impetus for the movement comes from the dancers' core; twisting and contracting torsos pull arms and legs along. As a result, the dancers look more like creatures than people. In the finale of "Grand Duo," Morris again illuminates the music's depth. Dancers speed through small gestures that look like child's play, but harsh rebounds and an intense focus bring forth the polka's dark undertones.

Harrison serves as Morris's muse again in the comedic, dynamic solo "Serenade," performed by the choreographer himself.

In each of the five movements, he plays with a different object, including a spectacular turn on the castanets in the final sonata. Now well into middle age and less than svelte, Morris still moves with a commanding fluidity. His shoulders rise, then roll down as he presents himself in true diva fashion.

The program opened with comedic flair. To Haydn's Horn Concerto No. 2, "A Lake" parodies "Swan Lake's" stately pretension. The dancers, who possess amazing buoyancy -- particularly lead David Leventhal -- skip through the jumps of classical swans.

Morris also recalls the famous ballet birds in arm movements: The dancers repeatedly raise their arms overhead, wrists touching just below drooping hands. Then their arms fall, drawn downward by melting elbows. Where the Harrison-accompanied works play with the music, "A Lake" closely follows its score, so the dance becomes a visual version of the music.

The final piece, "V," Morris's tribute to New York after Sept. 11, 2001, is one of his most powerful works. In part through choreographic genius and in part through careful selection of dancers, Morris imbues simple phrases and sections of rushing momentum with great power. Both appear in "V." To slower parts of Schumann's "Allegro Brillante," the cast members crawl toward each other, maintaining a straight line from head to foot. When they meet, some dancers rise individually to stand while others continue crawling, suggesting an evolution from baseness. In faster sections, dancers swoop through leaps, phrases usually ending with gently cradling partnering, the lifted dancer's arm stretching heavenward. At "V's" midpoint on Tuesday, a general lull occurred. Half the cast fought past the fatigue and danced even better, while the others chose a "get me through this" approach that resulted in sloppiness.

Mark Morris Dance Group performs "Grand Duo," one of two works set to music by Lou Harrison, at Wolf Trap.Mark Morris dancers perform "A Lake," a "Swan Lake" parody, at Wolf Trap.