  We define a number of new combinatorial operations on skew semistandard
domino tableaux, which together with constructions introduced earlier by C.
Carre and B. Leclerc, define an elegant structure on the set of these tableaux,
that closely parallels the structure defined in [math.CO/9908099] for ordinary
skew semistandard tableaux, that is related to the Littlewood-Richardson rule.
These operations are: (1) a bijection between semistandard domino tableaux and
certain pairs of ordinary tableaux of the same weight that together fill the
same shape; (2) a weight preserving transformation of domino tableaux to
ordinary tableaux of a related shape (the correspondence involves 2-quotients)
with the property that Yamanouchi domino tableaux correspond precisely to
Littlewood-Richardson tableaux; (3) a correspondence between Yamanouchi domino
tableaux of shape $\lambda$ and weight $\mu$ and Yamanouchi domino tableaux of
shape $\mu'$ and weight $\lambda$, where $\mu'$ is $\mu$ scaled by a factor 2.
The property at the heart of the structure so defined is that operations (1)
and (2) commute with the coplactic operations (implicitly) defined by Carre and
Leclerc. (1) elucidates their bijection analogous to that of Robinson (a.k.a.
the Robinson-Schensted correspondence), while the operation of moving chains in
domino tableaux underlying (2) is very similar to jeu de taquin.
