For New York dance-goers, this summer is a feast of “Sylvia” after decades of famine.

Two versions of this full-length ballet will take to the stage within weeks of each other. American Ballet Theatre will dance Frederick Ashton’s 1952 “Sylvia” from July 3 until July 6 at the Metropolitan Opera House. Then, from July 26 until July 28, the San Francisco Ballet will present the New York premiere of Mark Morris’s 2004 “Sylvia” at the New York State Theater, under the auspices of the Lincoln Center Festival.

Along with this embarrassment of riches comes a bit of a muddle: which to see? The best answer is … both.

The score, by Leo Delibes, has long been considered one of the supreme moments in ballet music. But for New Yorkers, “Sylvia” has been a great piece of ballet music in search of a ballet to accompany it. Until ABT imported Ashton’s “Sylvia” last year, the ballet was almost entirely absent from New York stages. So, enjoy the glut while it lasts.

Since its first production at the Paris Opera in 1876, “Sylvia” has paid tribute to the mythological ballets popular in the 18th century. Its plot is taken from Torquato Tasso’s 16th-century poem, which itself is a Renaissance sequel to the lineage of Greek and Roman pastoral poetry. And the plot reflects the twists and turns of a that body of literature.

Act I takes place in a sacred grove. Sylvia is an athletic nymph who has foresworn love because of her devotion to Diana, goddess of the hunt. But Sylvia is loved by the shepherd Aminta. She spurns him and is then abducted by a hunter, Orion, who takes her to his island hideaway. She won’t succumb to his attentions, however, because her heart now aches for the formerly rejected Aminta. Sylvia gets Orion drunk and appeals to Eros for help. He appears and takes her to a seacoast adjacent to the temple of Diana. Orion follows, and he and Aminta battle, while Sylvia barricades herself in Diana’s shrine. Diana is offended when Orion attempts to breach the doors of her sanctum to seize Sylvia and the goddess strikes down Orion. After initially opposing the amorous unity of Aminta and Sylvia – which is, after all, a betrayal of her code of celibacy – she finally blesses their wedding.

Ashton’s choreography and scheme for “Sylvia” reflect the desire to supply contemporary responses to the grand ballets of the 19th century, like “Sleeping Beauty.” The ballerina in the role of Sylvia fits into this mighty scene with heroic style. The choreography calls for athletic attack in Act I that turns into sultry abandon during Act II, and then into a lyricism in the crowning pas de deux of Act III.

San Francisco Ballet’s production is conceived on a somewhat more intimate scale. Mr. Morris, who began his training with folk dance, sees in “Sylvia” a new chapter in his careerlong illustration of communal solidarity in dance.

“Act I is about an all-female society, Act II an all-male society, and Act III is a fully realized community,” Mr. Morris wrote in Dance Magazine. The work surprised reviewers: Mr. Morris stuck to the story and did not add ironic spin, as he did on his earlier “Dido and Aeneas.” Another surprise – from this choreographer so well-known for modern dance – was the choice to work within the ballet impulse and put his “Sylvia” on pointe.

The central similarity in the works, however, is perhaps more striking than any difference. Ashton and Mr. Morris agree that it is love that makes the world go ’round. Their respective versions of “Sylvia” establish the character of Eros as the indispensable force setting the ballet on its axis, a figure – similar to the Lilac Fairy in “Sleeping Beauty” – that demonstrates ballet’s appropriation of the deus ex machina of ancient drama. For audience members eager for a double-header, the character of Eros will provide much food for thought.

In “Sylvia” we watch Eros’s irresistible allures work psychological reversals in the leading characters. At first, Sylvia mocks the god of love, as befits a handmaiden of Diana. Confronted by Aminta’s adoration, Sylvia turns her bow towards Eros. Aminta runs interference and takes the arrow for Eros, while Eros in turn aims his fabled arrow at Sylvia, who vanishes to nurse her wound, but returns onstage with a much more sympathetic response to Aminta.

Eros is conceived as a protean image, gifted with the transformative capacities of ancient deities. In Act I, local rustics grieve over Aminta, who seems mortally wounded by the arrow he’s taken for Eros. A mysterious figure appears onstage, dressed in a rustic smock. He ministers to Aminta, and now Eros throws off his smock and shows his true identity. The postmodern identities of Eros in Mr. Morris’s ballet are even more androgynous: His various disguises in clude a gold lame evening gown.

In Act II, Eros answers Sylvia’s call for help and pilots her to the vicinity of Diana’s temple. In Act III, it is Eros who overcomes Diana’s resistance to the wedding of Sylvia and Aminta, reminding the goddess that she, too, has not been entirely immune to the allure of love. Eros forcibly recalls for Diana her earlier dalliance with the shepherd Endymion.

The other great commonality between these two works is the glorious music. Delibes’s score is tuneful, fragrant, innovative for its use of Wagnerian motifs, as well as for its still-startling orchestration, which becomes almost disconcertingly contemporary in Act III by his pioneering use of the alto saxophone. And as New Yorkers will get to see this summer, listening to Delibes’s score is even better when there is a live ballet to go along with it.

American Ballet Theatre’s “Sylvia” will be performed from July 3 until July 6, at the Metropolitan Opera House (Lincoln Center, 212-362-6000). San Francisco Ballet’s “Sylvia” will be performed from July 26 until July 28 at the New York State Theater (Lincoln Center, 212-721-6500).