We represent the genus two free energy of an arbitrary semisimple Frobenius
manifold as a sum of contributions associated with dual graphs of certain
stable algebraic curves of genus two plus the so-called "genus two G-function".
Conjecturally the genus two G-function vanishes for a series of important
examples of Frobenius manifolds associated with simple singularities as well as
for P1-orbifolds with positive Euler characteristics. We explain the
reasons for such Conjecture and prove it in certain particular cases.Comment: 37 pages, 3 figures, V2: the published versio