Perhaps you know the 5th Dimension from its cover of two songs from the Hair soundtrack, the hippie-soul "Aquarius / Let the Sunshine In." Or perhaps the quintet is familiar because of its Jimmy Webb-penned uplift "Up, Up and Away," or for its stone-cold classic versions of Laura Nyro's "Stoned Soul Picnic" and "Wedding Bell Blues." You might not know, however, that the 5th Dimension's original lineup featured three St. Louis natives: Billy Davis, Jr., Lamonte McLemore and the late Ron Townson. Their pedigree explains why the group is receiving a star on the St. Louis Walk of Fame. At 11 a.m. on Thursday, March 18, an induction ceremony will take place at 6164 Delmar (across from the Moonrise Hotel). The living members of the 5th Dimension are scheduled to be there in person, and a ragtime band will also play. Incidentally, it's still a touring act, but only vocalist Florence LaRue remains from the original incarnation.