Those for whom classical ballet holds no other fascination may be finally won over by sex appeal. In addition to its artistic merits, which are very considerablee, "The Feld Ballet" on public TV's "Dance in America" series tonight at 9 on Channel 26-is rife with improbably long, slender legs and seductive torsos.

The limbs of the Feld Women, who tend to look like Seventeen models, seem to begin at the shoulder, and the men could easily be delegates to a surfing convention.

Both typical and exceptional is twinkly Michaela Hughes, all slinky flapper in Choreographer Eliot Feld's Gershwin opus, "The Real McCoy," all ingenuous eroticism in her pom-pom solo in "Half Time" Feld's starr-spangled salute to cheerleading.

Even in less overtly sexual contexts, Field's choreography has its voluptuous side-witness the swooning dips and ecstatic leg-splits if "Intermezzo."

In the televising of dance, "The Feld Ballet" goes beyond the already fine accomplishments of the DIA series. The dancing is seen from an ideal range and angle, and the lighting more closely approximates the contrasts and highlights of the theater than ever before.

The Feld repertory sampled here, which is intended to be "for and about all kinds of people," also makes excellent introductory material. It's a pity the program couldn't have been longer, though, to allow for more whole works instead of excerpts.