  We explain simple semi-classical rules to estimate the lifetime of any given
highly-excited quantum state of the string spectrum in flat spacetime. We
discuss both the decays by splitting into two massive states and by massless
emission. As an application, we study a solution describing a rotating and
pulsating ellipse which becomes folded at an instant of time -- the ``squashing
ellipse''. This string interpolates between the folded string with maximum
angular momentum and the pulsating circular string. We explicitly compute the
quantum decay rate for the corresponding quantum state, and verify the basic
rules that we propose. Finally, we give a more general (4-parameter) family of
closed string solutions representing rotating and pulsating elliptical strings.
