St. Vincent and David Byrne marked today's arrival of their 'Love This Giant' collaborative album a day early by stopping by 'Late Night With Jimmy Fallon' last night and playing not one, but two songs off the disc: 'Who,' which aired on the actual show and marked the duo's network television debut, and 'The Forest Awakes,' which was filmed as a web exclusive.

Backed by an eight-piece horn section, a synth/sampler player and a drummer, 'Who' (watch above) features the ex-Polyphonic Spree singer Annie Clark and the former Talking Heads frontman trading guitar licks -- she on electric, he on acoustic -- and swapping verses with the natural flow of longtime collaborators. 'The Forest Awakes' (embedded below), meanwhile, features the same basic backing instrumentation, with St. Vincent taking on lead vocal duties and Byrne providing some post-punk guitar twang and the occasional backup vocal.

The pair kick off a fall 2012 North American theater tour on Saturday (Sept. 15) in Minneapolis, Minn., and will be on the road together through an Oct. 20 date in Vancouver, British Columbia. Check out their itinerary here. In the meantime, click here to check out the black-and-white video for 'Who' shot by Danish director Martin de Thurah, which finds Byrne encountering a lifeless Clark in the middle of the road and then teaching her some dance moves.

Watch St. Vincent and David Byrne Perform 'The Forest Awakes' on 'Jimmy Fallon'