  An involution in a Coxeter group has an associated set of involution words, a
variation on reduced words. These words are saturated chains in a partial order
first considered by Richardson and Springer in their study of symmetric
varieties. In the symmetric group, involution words can be enumerated in terms
of tableaux using appropriate analogues of the symmetric functions introduced
by Stanley to accomplish the same task for reduced words. We adapt this
approach to the group of signed permutations. We show that involution words for
the longest element in the Coxeter group $C_n$ are in bijection with reduced
words for the longest element in $A_n = S_{n+1}$, which are known to be in
bijection with standard tableaux of shape $(n, n-1, \ldots, 2, 1)$.
