  The free non-critical string quantum model is constructed directly in the
light-cone variables in the range of dimensions $1<D<25$. The longitudinal
degrees of freedom are described by an abstract Verma module. The central
charge of this module is restricted by the requirement of the closure of the
nonlinear realization of the Poincare algebra. The spin content of the model is
analysed. In particular for D=4 the explicit formulae for the character
generating functions of the open and closed massive strings are given and the
spin spectrum of first 12 excited levels is calculated. It is shown that for
the space-time dimension in the range $1<D<25$ the non-critical light-cone
string is equivalent to the critical massive string and to the non-critical
Nambu-Goto string.
