This paper continues the study of the structures induced on the "invisible boundary" of the modular tower and extends some results of [MaMar1]. We start with a systematic formalism of pseudo-measures generalizing the wellknown theory of modular symbols for SL(2). These pseudo-measures, and the related integral formula which we call the Lévy-Mellin transform, can be considered as an "∞-adic" version of Mazur's p-adic measures that have been introduced in the seventies in the theory of p-adic interpolation of the Mellin transforms of cusp forms, cf. [Ma2]. A formalism of iterated Lévy-Mellin transform in the style of [Ma3] is sketched. Finally, we discuss the invisible boundary from the perspective of non-commutative geometry.
Definition.A pseudo-measure on P 1 (R) with values in a commutative group (written additively) W is a function µ : P 1 (Q) × P 1 (Q) → W satisfying the following conditions: for any α, β, γ ∈ P 1 (Q), µ(α, α) = 0, µ(α, β) + µ(β, α) = 0 , (1.1) µ(α, β) + µ(β, γ) + µ(γ, α) = 0 .( 1.2)