In the case of an interacting Hamiltonian with a Zdependence such as the He isoelectronic series, increasing the nuclear charge corresponds to gradually turning off the interaction . It seems plausible that approaching the Z → ∞ there would inherently change the nature of the quantum system and lead to non-analiticities in analogy to the M → ∞ limit in the electro-nuclear case. This conjecture needs to be tested and will be the subject of future study.