Collection. The two whole-tone collections (WT₀ = C, D, E, F♯, G♯, A♯ and WT₁ = C♯, D♯, F, G, A, B) play an important role in this music. In the opening melody, four notes (mostly the higher notes) are drawn from WT₀ while two (B and C♯) are from WT₁. In the contrasting collection in m. 5, the highest and lowest four notes are from WT₁, while the inner two (E and F♯) are from WT₀.