  We speculate that glass-forming liquids may contain fairly large and
well-defined crystallites. This is based on arguing that the slowly relaxing
"frozen-in" stresses characterizing ultraviscous liquids increase the barrier
for nucleation, thus allowing for larger unstable crystallites than otherwise
possible. The frozen-in stresses also deform the crystallites, making their
observation difficult; specifically it is argued that a situation where 1/N of
the molecules form N X N X N crystallites would be hard to detect by standard
X-ray or neutron scattering experiments.
