  It was recently shown that non-Abelian vortex strings supported in a version
of four-dimensional N=2 supersymmetric QCD (SQCD) become critical superstrings.
In addition to four translational moduli, non-Abelian strings under
consideration have six orientational and size moduli. Together they form a
ten-dimensional target space required for a superstring to be critical, namely,
the product of the flat four-dimensional space and conifold -- a non-compact
Calabi-Yau threefold. In this paper we report on further studies of low-lying
closed string states which emerge in four dimensions and identify them as
hadrons of our four-dimensional N=2 SQCD. We use the approach based on "little
string theory," describing critical string on the conifold as a non-critical
$c=1$ string with the Liouville field and a compact scalar at the self-dual
radius. In addition to massless hypermultiplet found earlier we observe several
massive vector multiplets and a massive spin-2 multiplet, all belonging to the
long (non-BPS) representations of N=2 supersymmetry in four dimensions. All the
above states are interpreted as baryons formed by a closed string with confined
monopoles attached. Our construction presents an example of a "reverse
holography."
