What makes the Mark Morris Dance Group different from most other professional dance companies is its acquiescence to the id. Mr. Morris’s choreography, even though it is manifestly structured, allows the excellently trained dancers to seem to be doing just what they want: thrashing, flailing, jabbing, and lobbing attitude in a kind of collective release from constraint, inhibition, and learned behavior.

Mr. Morris’s company celebrates its 25th anniversary this year, and Wednesday night’s opening of the company’s three-week season at the Brooklyn Academy of Music showcased works created by Mr. Morris over a span of 20 years.The program opened with “V,” created in 2001, continued with “Grand Duo” from 1993, and then closed with “Gloria,” made in 1981. All three dances saw the extensive presence of dancers recumbent on the floor, propelling themselves in crawls, slithers, or inchworm undulations – generally suggesting a collective desire to revert to something primordial.

“V” is set to Schumann’s Quintet in E flat for Piano and Strings. In it, Mr. Morris employs vocabulary of the Romantic ballet that was at its zenith in the 1840s, when Schumann composed his quintet, but the articulation is limper, and the legs are for the most part turned in and the feet left unpointed.

The piece begins with dances silhouetted in puppet-like tilts.Wearing flowing, flaring tops that are like abbreviated nightshirts and give the feeling of a pajama party, the dancers billow as much as their costumes. There is a spongy, soft-centered quality to their movement.

There are two teams of dancers, one dressed in green, one in blue, each relay supplanting, partnering, and intermixing with their opposite contingent. Mr. Morris likes to contrast regimentation with quotidian ordinariness, and dancers also walk on and off casually. The dancers flap their arms, fold them into their bodies, then extend them somewhat semaphorically as if to say “Here we are!” Sometimes their arms are circled in rings that suggest an embrace; at other moments, their arms aspire to transform into drapery.

As “V” concludes, the dancers seem more invertebrate than ever, rippling and fluttering. Free-form flings of the arms surmount legs performing balletic cabrioles; staccato accent is introduced by occasional jabs of the arms over spinning chain turns.

Mr. Morris has frequently choreographed to the music of Lou Harrison, whose “Grand Duo for Violin and Piano” provides a varied musical platform for the choreographer’s “Grand Duo.” Mr. Morris creates step-crowded movements as well as ones in which the dancers slink and undulate. “Grand Duo” starts out resembling “Marat Sade” but culminates in communal affirmation.

When the curtain rises, we see some in the ensemble facing us, some facing away.They are lone, impervious, autonomous units, their movement almost aleatoric as a moody nocturne is sounded. The dancers shuffle offstage, then they migrate into factions that are at times antagonistic. They are canted figures as they assemble in pointy-fingered Shiva positions, and then, in a climactic bacchanal, they slap their midriffs like folk dancers. Arrayed on the floor, they conduct a pow-wow before the piece ends abruptly.

“Gloria” demonstrates the profound influence of Paul Taylor on Mr. Morris’s work.The piece could not have been made had Mr. Taylor not created “Esplanade” six years earlier. Like “Esplanade,” “Gloria” sets “modern” perambulations – walking, running, armswinging, and gymnastic slides and skids – to Baroque music. Mr. Morris also quotes from the familial huddles of “Esplanade,” the dancers shifting on each note from one freighted emotional pose to another. In “Gloria,” we also see dancers hurtling to the ground contrasted with a detachment ambling in single file across the back of the stage.

Early in the piece, dancers are paddling on the floor like surfers or slithering to suggest amphibious creatures, dragging themselves across the stage like walking catfish. Two dancers administer to two others, prone and momentarily still, explicating a theme of falling and resurrection. Despite the precedent set by Mr. Taylor, it was nonetheless audacious of Mr. Morris to set this rooted-to-the-ground movement to Vivaldi’s gently soaring “Gloria in D.”

“Gloria” also demonstrates Mr. Morris’s humor. Jump-rope arms accompany a parallel assemble hop into the wings, iterating a classic Morris theme in which dancers linger at the periphery of the stage picture, momentarily arrested in a threshold indecision, seeming to be half into the wings, half onstage. Cradled in a man’s arms, a woman is carried onstage and deposited into the waiting arms of another dancer, before her original conveyer disappears immediately back into the wings from where they emerged.

The deference to the id that marks the Morris aesthetic extends to Mr. Morris’s decision to conduct “Gloria.” Live accompaniment, as always, lends an atmosphere of luxe to his performances. The MMDG Music Ensemble and the Juilliard Choral Union with soloists Eileen Clark and Margaret Bragle were very supportive of his conducting debut, as was the rapt first-night audience – and he certainly did no harm.

How much it added to the artistic caliber of the evening is open to question. Yet Mr. Morris apparently wanted to do it, and so he did.

Until March 28 at the Mark Morris Dance Theater (Brooklyn Academy of Music, 718-636-4100).